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-rw-r--r--doc/cli/test.sh106
-rw-r--r--doc/debian.conntrackd.init.d48
-rw-r--r--doc/manual/Makefile4
-rw-r--r--doc/manual/config.xsl10
-rw-r--r--doc/manual/conntrack-tools.html202
-rw-r--r--doc/manual/conntrack-tools.tmpl577
-rw-r--r--doc/manual/docbook.css43
-rw-r--r--doc/stats/conntrackd.conf140
-rw-r--r--doc/stats/conntrackd.conf.orig121
-rw-r--r--doc/sync/alarm/README1
-rw-r--r--doc/sync/alarm/conntrackd.conf372
-rw-r--r--doc/sync/alarm/conntrackd.conf.orig348
-rw-r--r--doc/sync/alarm/conntrackd.conf.rej30
-rw-r--r--doc/sync/ftfw/README1
-rw-r--r--doc/sync/ftfw/conntrackd.conf397
-rw-r--r--doc/sync/ftfw/conntrackd.conf.orig370
-rw-r--r--doc/sync/keepalived-multi1.conf71
-rw-r--r--doc/sync/keepalived-multi2.conf71
-rw-r--r--doc/sync/keepalived.conf43
-rwxr-xr-xdoc/sync/multiprimary.sh212
-rw-r--r--doc/sync/notrack/README3
-rw-r--r--doc/sync/notrack/conntrackd.conf434
-rwxr-xr-xdoc/sync/primary-backup.sh124
23 files changed, 3728 insertions, 0 deletions
diff --git a/doc/cli/test.sh b/doc/cli/test.sh
new file mode 100644
index 0000000..2a0fef7
--- /dev/null
+++ b/doc/cli/test.sh
@@ -0,0 +1,106 @@
+CONNTRACK=conntrack
+
+SRC=1.1.1.1
+DST=2.2.2.2
+SPORT=2005
+DPORT=21
+
+case $1 in
+ dump)
+ echo "Dumping conntrack table"
+ $CONNTRACK -L
+ ;;
+ flush)
+ echo "Flushing conntrack table"
+ $CONNTRACK -F
+ ;;
+ new)
+ echo "creating a new conntrack"
+ $CONNTRACK -I --orig-src $SRC --orig-dst $DST \
+ --reply-src $DST --reply-dst $SRC -p tcp \
+ --orig-port-src $SPORT --orig-port-dst $DPORT \
+ --reply-port-src $DPORT --reply-port-dst $SPORT \
+ --state LISTEN -u SEEN_REPLY -t 50
+ ;;
+ new-simple)
+ echo "creating a new conntrack (simplified)"
+ $CONNTRACK -I -s $SRC -d $DST \
+ -p tcp --sport $SPORT --dport $DPORT \
+ --state LISTEN -u SEEN_REPLY -t 50
+ ;;
+ new-nat)
+ echo "creating a new conntrack (NAT)"
+ $CONNTRACK -I -s $SRC -d $DST \
+ -p tcp --sport $SPORT --dport $DPORT \
+ --state LISTEN -u SEEN_REPLY -t 50 --dst-nat 8.8.8.8
+ ;;
+ get)
+ echo "getting a conntrack"
+ $CONNTRACK -G -s $SRC -d $DST \
+ -p tcp --sport $SPORT --dport $DPORT
+ ;;
+ change)
+ echo "change a conntrack"
+ $CONNTRACK -U -s $SRC -d $DST \
+ -p tcp --sport $SPORT --dport $DPORT \
+ --state TIME_WAIT -u ASSURED,SEEN_REPLY -t 500
+ ;;
+ delete)
+ $CONNTRACK -D -s $SRC -d $DST \
+ -p tcp --sport $SPORT --dport $DPORT
+ ;;
+ output)
+ proc=$(cat /proc/net/ip_conntrack | wc -l)
+ netl=$($CONNTRACK -L | wc -l)
+ count=$(cat /proc/sys/net/ipv4/netfilter/ip_conntrack_count)
+ if [ $proc -ne $netl ]; then
+ echo "proc is $proc and netl is $netl and count is $count"
+ else
+ if [ $proc -ne $count ]; then
+ echo "proc is $proc and netl is $netl and count is $count"
+ else
+ echo "now $proc"
+ fi
+ fi
+ ;;
+ dump-expect)
+ $CONNTRACK -L expect
+ ;;
+ flush-expect)
+ $CONNTRACK -F expect
+ ;;
+ create-expect)
+ # requires modprobe ip_conntrack_ftp
+ $CONNTRACK -I expect --orig-src $SRC --orig-dst $DST \
+ --tuple-src 4.4.4.4 --tuple-dst 5.5.5.5 \
+ --mask-src 255.255.255.0 --mask-dst 255.255.255.255 \
+ -p tcp --orig-port-src $SPORT --orig-port-dst $DPORT \
+ -t 200 --tuple-port-src 10240 --tuple-port-dst 10241\
+ --mask-port-src 10 --mask-port-dst 300
+ ;;
+ get-expect)
+ $CONNTRACK -G expect --orig-src 4.4.4.4 --orig-dst 5.5.5.5 \
+ --p tcp --orig-port-src 10240 --orig-port-dst 10241
+ ;;
+ delete-expect)
+ $CONNTRACK -D expect --orig-src 4.4.4.4 \
+ --orig-dst 5.5.5.5 -p tcp --orig-port-src 10240 \
+ --orig-port-dst 10241
+ ;;
+ *)
+ echo "Usage: $0 [dump"
+ echo " |new"
+ echo " |new-simple"
+ echo " |new-nat"
+ echo " |get"
+ echo " |change"
+ echo " |delete"
+ echo " |output"
+ echo " |flush"
+ echo " |dump-expect"
+ echo " |flush-expect"
+ echo " |create-expect"
+ echo " |get-expect"
+ echo " |delete-expect]"
+ ;;
+esac
diff --git a/doc/debian.conntrackd.init.d b/doc/debian.conntrackd.init.d
new file mode 100644
index 0000000..ba847dd
--- /dev/null
+++ b/doc/debian.conntrackd.init.d
@@ -0,0 +1,48 @@
+#!/bin/sh
+#
+# /etc/init.d/conntrackd
+#
+# Maximilian Wilhelm <max@rfc2324.org>
+# -- Mon, 06 Nov 2006 18:39:07 +0100
+#
+
+export PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
+
+NAME="conntrackd"
+DAEMON=`command -v conntrackd`
+CONFIG="/etc/conntrack/conntrackd.conf"
+PIDFILE="/var/run/${NAME}.pid"
+
+
+# Gracefully exit if there is no daemon (debian way of life)
+if [ ! -x "${DAEMON}" ]; then
+ exit 0
+fi
+
+# Check for config file
+if [ ! -f /etc/conntrackd/conntrackd.conf ]; then
+ echo "Error: There is no config file for $NAME" >&2
+ exit 1;
+fi
+
+case "$1" in
+ start)
+ echo -n "Starting $NAME: "
+ start-stop-daemon --start --quiet --make-pidfile --pidfile "/var/run/${NAME}.pid" --background --exec "${DAEMON}" && echo "done." || echo "FAILED!"
+ ;;
+ stop)
+ echo -n "Stopping $NAME:"
+ start-stop-daemon --stop --quiet --oknodo --pidfile "/var/run/${NAME}.pid" && echo "done." || echo "FAILED!"
+ ;;
+
+ restart)
+ $0 start
+ $0 stop
+ ;;
+
+ *)
+ echo "Usage: /etc/init.d/conntrackd {start|stop|restart}"
+ exit 1
+esac
+
+exit 0
diff --git a/doc/manual/Makefile b/doc/manual/Makefile
new file mode 100644
index 0000000..bd179a6
--- /dev/null
+++ b/doc/manual/Makefile
@@ -0,0 +1,4 @@
+html-no-chunks:
+ xmlto xhtml-nochunks -m config.xsl conntrack-tools.tmpl
+clean:
+ rm -f conntrack-tools.html
diff --git a/doc/manual/config.xsl b/doc/manual/config.xsl
new file mode 100644
index 0000000..04722a5
--- /dev/null
+++ b/doc/manual/config.xsl
@@ -0,0 +1,10 @@
+<?xml version='1.0'?>
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+ xmlns:fo="http://www.w3.org/1999/XSL/Format"
+ version="1.0">
+ <xsl:param name="use.id.as.filename" select="'1'"/>
+ <xsl:param name="admon.graphics" select="'1'"/>
+ <xsl:param name="admon.graphics.path"></xsl:param>
+ <xsl:param name="chunk.section.depth" select="0"></xsl:param>
+ <xsl:param name="html.stylesheet" select="'docbook.css'"/>
+</xsl:stylesheet>
diff --git a/doc/manual/conntrack-tools.html b/doc/manual/conntrack-tools.html
new file mode 100644
index 0000000..c2702b1
--- /dev/null
+++ b/doc/manual/conntrack-tools.html
@@ -0,0 +1,202 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>The conntrack-tools user manual</title><link rel="stylesheet" href="docbook.css" type="text/css" /><meta name="generator" content="DocBook XSL Stylesheets V1.72.0" /></head><body><div class="book" lang="en" xml:lang="en"><div class="titlepage"><div><div><h1 class="title"><a id="conntrack-tools-how-to"></a>The conntrack-tools user manual</h1></div><div><div class="authorgroup"><div class="author"><h3 class="author"><span class="firstname">Pablo</span> <span class="surname">Neira Ayuso</span></h3><div class="affiliation"><div class="address"><p><br />
+      <code class="email">&lt;<a href="mailto:pablo@netfilter.org">pablo@netfilter.org</a>&gt;</code><br />
+     </p></div></div></div></div></div><div><p class="releaseinfo">
+ This document details how to install and configure the
+ <a href="http://conntrack-tools.netfilter.org" target="_top">conntrack-tools</a>
+ 0.9.8. This software is under development, for that reason, it is likely
+ that this document will evolve in the future to cover new features and
+ changes.</p></div><div><p class="copyright">Copyright © 2008 Pablo Neira Ayuso</p></div><div><div class="legalnotice"><a id="id2592572"></a><p>
+ Permission is granted to copy, distribute and/or modify this document
+ under the terms of the GNU Free Documentation License, Version 1.2
+ or any later version published by the Free Software Foundation;
+ with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+ A copy of the license is included in the section entitled "GNU
+ Free Documentation License".
+ </p></div></div></div><hr /></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="chapter"><a href="#introduction">1. Introduction</a></span></dt><dt><span class="chapter"><a href="#what">2. What are the conntrack-tools?</a></span></dt><dt><span class="chapter"><a href="#requirements">3. Requirements</a></span></dt><dt><span class="chapter"><a href="#Installation">4. Installation</a></span></dt><dt><span class="chapter"><a href="#conntrack">5. Using conntrack: the command line interface</a></span></dt><dt><span class="chapter"><a href="#settingup">6. Setting up conntrackd: the daemon</a></span></dt><dd><dl><dt><span class="sect1"><a href="#sync">State table synchronization</a></span></dt><dd><dl><dt><span class="sect2"><a href="#sync-requirements">Requirements</a></span></dt><dt><span class="sect2"><a href="#sync-configure">Configuring the daemon</a></span></dt><dt><span class="sect2"><a href="#sync-pb">Active-Backup setup</a></span></dt><dt><span class="sect2"><a href="#sync-aa">Active-Active setup</a></span></dt><dt><span class="sect2"><a href="#sync-launch">Launching conntrackd</a></span></dt><dt><span class="sect2"><a href="#sync-trouble">Troubleshooting</a></span></dt></dl></dd></dl></dd></dl></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="introduction"></a>Chapter 1. Introduction</h2></div></div></div><p>This document should be a kick-off point to install and configure the
+ <a href="http://conntrack-tools.netfilter.org" target="_top">conntrack-tools</a>.
+ If you find any error or imprecision in this document, please send an email
+ to the author, it will be appreciated.</p><p>In this document, the author assumes that the reader is familiar with firewalling concepts and iptables in general. If this is not your case, I suggest you to read the iptables documentation before going ahead. Moreover, the reader must also understand the difference between <span class="emphasis"><em>stateful</em></span> and <span class="emphasis"><em>stateless</em></span> firewalls. If this is not your case, I strongly suggest you to read the article <a href="http://people.netfilter.org/pablo/docs/login.pdf" target="_top">Netfilter's Connection Tracking System</a> published in <span class="emphasis"><em>:login; the USENIX magazine</em></span>. That document contains a general description that should help to clarify the concepts.</p><p>If you do not fulfill the previous requirements, this documentation is likely to be a source of frustration. Probably, you wonder why I'm insisting on these prerequisites too much, the fact is that if your iptables rule-set is <span class="emphasis"><em>stateless</em></span>, it is very likely that the <span class="emphasis"><em>conntrack-tools</em></span> will not be of any help for you. You have been warned!</p></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="what"></a>Chapter 2. What are the conntrack-tools?</h2></div></div></div><p>The conntrack-tools are a set of free software tools for GNU/Linux that allow system administrators interact, from user-space, with the in-kernel <a href="http://people.netfilter.org/pablo/docs/login.pdf" target="_top">Connection Tracking System</a>, which is the module that enables stateful packet inspection for iptables. Probably, you did not hear about this module so far. However, if any of the rules of your rule-set use the <span class="emphasis"><em>state</em></span> or <span class="emphasis"><em>ctstate</em></span> iptables matches, you are indeed using it.
+
+ </p><p>The <a href="http://conntrack-tools.netfilter.org" target="_top">conntrack-tools</a> package contains two programs:</p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>conntrack</em></span> is command line interface conntrack provides a more flexible interface to the connnection tracking system than /proc/net/ip_conntrack. With conntrack, you can show, delete and update the existing state entries; and you can also listen to flow events.</p></li><li><p><span class="emphasis"><em>conntrackd</em></span> is the user-space connection tracking daemon. This daemon can be used to deploy fault-tolerant GNU/Linux firewalls but you can also use it to collect flow-based statistics of the firewall use.</p></li></ul></div><p>Although the name of both tools is very similar - and you can blame me for that, I'm not a marketing guy - they are used for very different tasks.</p></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="requirements"></a>Chapter 3. Requirements</h2></div></div></div><p>You have to install the following software in order to get the <span class="emphasis"><em>conntrack-tools</em></span> working. Make sure that you have installed them correctly before going ahead:</p><div class="itemizedlist"><ul type="disc"><li><p><a href="http://www.kernel.org" target="_top">Linux kernel</a> version &gt;= 2.6.18 that, at least, has support for:</p><div class="itemizedlist"><ul type="circle"><li><p>Connection Tracking System.</p><div class="itemizedlist"><ul type="square"><li><p>CONFIG_NF_CONNTRACK=m</p></li><li><p>CONFIG_NF_CONNTRACK_IPV4=m</p></li><li><p>CONFIG_NF_CONNTRACK_IPV6=m (if your setup supports IPv6)</p></li></ul></div></li><li><p>nfnetlink: the generic messaging interface for Netfilter.</p><div class="itemizedlist"><ul type="square"><li><p>CONFIG_NETFILTER_NETLINK=m</p></li></ul></div></li><li><p>nf_conntrack_netlink: the messaging interface for the Connection Tracking System.</p><div class="itemizedlist"><ul type="square"><li><p>CONFIG_NF_CT_NETLINK=m</p></li></ul></div></li><li><p>connection tracking event notification API: the flow-based event notification interface.</p><div class="itemizedlist"><ul type="square"><li><p>CONFIG_NF_CONNTRACK_EVENTS=y</p></li></ul></div></li></ul></div><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0" summary="Note: Verifying kernel support"><tr><td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="note.png" /></td><th align="left">Verifying kernel support</th></tr><tr><td align="left" valign="top"><p>
+ Make sure you have loaded <span class="emphasis"><em>nf_conntrack</em></span>, <span class="emphasis"><em>nf_conntrack_ipv4</em></span> (if your setup also supports IPv6, <span class="emphasis"><em>nf_conntrack_ipv6</em></span>) and <span class="emphasis"><em>nf_conntrack_netlink</em></span>.
+ </p></td></tr></table></div></li><li><p>libnfnetlink: the netfilter netlink library use the official release available in <a href="http://www.netfilter.org" target="_top">netfilter.org</a></p></li><li><p>libnetfilter_conntrack: the netfilter netlink library use the official release available in <a href="http://www.netfilter.org" target="_top">netfilter.org</a></p></li></ul></div></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="Installation"></a>Chapter 4. Installation</h2></div></div></div><p>To compile and install the <span class="emphasis"><em>conntrack-tools</em></span> run the following commands:</p><pre class="programlisting">
+ (non-root)$ tar xvjf conntrack-tools-x.x.x.tar.bz2
+ (non-root)$ cd conntrack-tools-x.x.x
+ (non-root)$ ./configure --prefix=/usr
+ (non-root)$ make
+ (root) # make install</pre><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0" summary="Note: Fedora Users"><tr><td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="note.png" /></td><th align="left">Fedora Users</th></tr><tr><td align="left" valign="top"><p>If you are installing the libraries in /usr/local/, do not forget to do the following things:</p><div class="itemizedlist"><ul type="disc"><li><p>PKG_CONFIG_PATH=/usr/local/lib/pkgconfig; export PKG_CONFIG_PATH</p></li><li><p>Add `/usr/local/lib' to your /etc/ld.so.conf file and run `ldconfig'</p></li></ul></div><p>Check `ldd' for trouble-shooting, read <a href="http://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html" target="_top">this</a> for more information on how libraries work.</p></td></tr></table></div><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0" summary="Note: Verifying kernel support"><tr><td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="note.png" /></td><th align="left">Verifying kernel support</th></tr><tr><td align="left" valign="top"><p>To check that the modules are enabled in the kernel, run <span class="emphasis"><em>`conntrack -E'</em></span> and generate traffic, you should see flow events reporting new connections and updates.
+ </p></td></tr></table></div></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="conntrack"></a>Chapter 5. Using conntrack: the command line interface</h2></div></div></div><p>The <span class="emphasis"><em>/proc/net/ip_conntrack</em></span> interface is very limited as it only allows you to display the existing flows, their state and other information:</p><pre class="programlisting">
+ # cat /proc/net/ip_conntrack
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=0 secmark=0 use=1
+ tcp 6 431698 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34849 dport=993 packets=244 bytes=18723 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34849 packets=203 bytes=144731 [ASSURED] mark=0 secmark=0 use=1
+ </pre><p>The command line tool <span class="emphasis"><em>conntrack</em></span> can be used to display the same information:</p><pre class="programlisting">
+ # conntrack -L
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=0 secmark=0 use=1
+ tcp 6 431698 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34849 dport=993 packets=244 bytes=18723 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34849 packets=203 bytes=144731 [ASSURED] mark=0 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 2 flow entries has been shown.
+ </pre><p>You can natively filter the output without using <span class="emphasis"><em>grep</em></span>:</p><pre class="programlisting">
+ # conntrack -L -p tcp --dport 34856
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=0 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 1 flow entries has been shown.
+ </pre><p>Update the mark based on a selection, this allows you to change the mark of an entry without using the CONNMARK target:</p><pre class="programlisting">
+ # conntrack -U -p tcp --dport 3486 --mark 10
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=1 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 1 flow entries has been updated.
+ </pre><p>Delete one entry, this can be used to block traffic (you have to set <span class="emphasis"><em>/proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_be_liberal</em></span> to zero).</p><pre class="programlisting">
+ # conntrack -D -p tcp --dport 3486
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=1 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 1 flow entries has been deleted.
+ </pre><p>Display the connection tracking events:</p><pre class="programlisting">
+ # conntrack -E
+ [NEW] udp 17 30 src=192.168.2.100 dst=192.168.2.1 sport=57767 dport=53 [UNREPLIED] src=192.168.2.1 dst=192.168.2.100 sport=53 dport=57767
+ [UPDATE] udp 17 29 src=192.168.2.100 dst=192.168.2.1 sport=57767 dport=53 src=192.168.2.1 dst=192.168.2.100 sport=53 dport=57767
+ [NEW] tcp 6 120 SYN_SENT src=192.168.2.100 dst=66.102.9.104 sport=33379 dport=80 [UNREPLIED] src=66.102.9.104 dst=192.168.2.100 sport=80 dport=33379
+ [UPDATE] tcp 6 60 SYN_RECV src=192.168.2.100 dst=66.102.9.104 sport=33379 dport=80 src=66.102.9.104 dst=192.168.2.100 sport=80 dport=33379
+ [UPDATE] tcp 6 432000 ESTABLISHED src=192.168.2.100 dst=66.102.9.104 sport=33379 dport=80 src=66.102.9.104 dst=192.168.2.100 sport=80 dport=33379 [ASSURED]
+</pre><p>You can also display the existing flows in XML format, filter the output based on the NAT handling applied, etc.</p></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="settingup"></a>Chapter 6. Setting up conntrackd: the daemon</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="#sync">State table synchronization</a></span></dt><dd><dl><dt><span class="sect2"><a href="#sync-requirements">Requirements</a></span></dt><dt><span class="sect2"><a href="#sync-configure">Configuring the daemon</a></span></dt><dt><span class="sect2"><a href="#sync-pb">Active-Backup setup</a></span></dt><dt><span class="sect2"><a href="#sync-aa">Active-Active setup</a></span></dt><dt><span class="sect2"><a href="#sync-launch">Launching conntrackd</a></span></dt><dt><span class="sect2"><a href="#sync-trouble">Troubleshooting</a></span></dt></dl></dd></dl></div><p>The daemon <span class="emphasis"><em>conntrackd</em></span> supports two working modes:</p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>State table synchronization</em></span>: the daemon can be used to synchronize the connection tracking state table between several firewall replicas. This can be used to deploy fault-tolerant stateful firewalls. This is the main feature of the daemon.</p></li><li><p><span class="emphasis"><em>Flow-based statistics collection</em></span>: the daemon can be used to collect flow-based statistics. This feature is similar to what <a href="http://www.netfilter.org/projects/ulogd2/" target="_top">ulogd-2.x</a> provides.</p></li></ul></div><div class="sect1" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="sync"></a>State table synchronization</h2></div></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="sync-requirements"></a>Requirements</h3></div></div></div><p>In order to get <span class="emphasis"><em>conntrackd</em></span> working in synchronization mode, you have to fulfill the following requirements:</p><div class="orderedlist"><ol type="1"><li><p>A <span class="emphasis"><em>high availability manager</em></span> like <a href="http://www.keepalived.org" target="_top">keepalived</a> that manages the virtual IPs of the
+ firewall cluster, detects errors, and decide when to migrate the virtual IPs
+ from one firewall replica to another. Without it, <span class="emphasis"><em>conntrackd</em></span> will not work appropriately.</p><p>The state synchronization setup requires a working installation of <a href="http://www.keepalived.org" target="_top">keepalived</a>, preferibly a recent version. Check if your distribution comes with a recent packaged version. Otherwise, you may compile it from the sources.
+ </p><p>
+ There is a very simple example file in the <span class="emphasis"><em>conntrackd</em></span>
+ sources to setup a simple HA cluster with keepalived (see the file
+ keepalived.conf under the doc/sync/ directory). This file can be used to
+ set up a simple VRRP cluster composed of two machines that hold the virtual
+ IPs 192.168.0.100 on eth0 and 192.168.1.100 on eth1.</p><p>If you are not familiar with <span class="emphasis"><em>keepalived</em></span>, please
+ read the official documentation available at the keepalived website
+ (<a href="http://www.keepalived.org" target="_top">http://www.keepalived.org</a>).</p><p>If you use a different high availability manager, make sure it works correctly before going ahead.</p></li><li><p>A dedicated link. The dedicated link between the firewalls is used
+ to transmit and receive the state information. The use of a dedicated link
+ is mandatory for security reasons as someone may pick the state information
+ that is transfered between the firewalls.</p></li><li><p>A well-formed stateful rule-set. Otherwise you are likely to experience
+ problems during the fail-over. An example of a well-formed stateful iptables
+ rule-set is available in the <a href="http://conntrack-tools.netfilter.org/testcase.html" target="_top">conntrack-tools website</a>.</p></li><li><p>If your Linux kernel is &lt; 2.6.22, you have to disable TCP window
+ tracking:
+ </p><pre class="programlisting">
+ # echo 1 &gt; /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_be_liberal
+ </pre><p>
+ </p></li></ol></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="sync-configure"></a>Configuring the daemon</h3></div></div></div><p>The daemon <span class="emphasis"><em>conntrackd</em></span> in synchronization mode
+ supports up to three replication approaches:</p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>notrack</em></span>: this approach is the most simple as
+ it is based on a best effort replication protocol, ie. unreliable
+ protocol. This protocol sends and receives the state information
+ without performing any specific checking.
+ </p></li><li><p><span class="emphasis"><em>ft-fw</em></span>: this approach is based on a reliable
+ protocol that performs message tracking. Thus, the protocol can recover
+ from message loss, re-ordering and corruption.</p></li><li><p><span class="emphasis"><em>alarm</em></span>: this approach is spamming. It is based
+ on a alarm-based protocol that periodically re-sends the flow state to
+ the backup firewall replicas. This protocol consumes a lot of bandwidth
+ but it resolves synchronization problems fast.</p></li></ul></div><p>The three existing approaches are soft real-time asynchronous
+ replication protocols that are aimed to have negligible impact in terms
+ of latency and bandwidth throughput in the stateful firewall filtering.</p><p>To configure <span class="emphasis"><em>conntrackd</em></span> in any of the existing
+ synchronization modes, you have to copy the example configuration file to
+ the directory /etc/conntrackd/ on every firewall replica. Note that
+ <span class="emphasis"><em>_type_</em></span> is the synchronization type selected.</p><pre class="programlisting">
+ (conntrack-tools-x.x.x)# cp doc/_type_/conntrackd.conf /etc/conntrackd/conntrackd.conf
+</pre><p>
+ Do not forget to edit the files before going ahead. There are several
+ parameters that you have to tune to adapt the example configuration file
+ to your setup.
+</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0" summary="Note: Configuration file location"><tr><td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="note.png" /></td><th align="left">Configuration file location</th></tr><tr><td align="left" valign="top"><p>If you don't want to put the config file under /etc/conntrackd/, just tell conntrackd where to find it passing the option -C.</p></td></tr></table></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="sync-pb"></a>Active-Backup setup</h3></div></div></div><p>In the Active-Backup setup, one of the stateful firewall replicas
+ filters traffic and the other acts as backup. If you use this approach,
+ you have to copy the script <span class="emphasis"><em>primary-backup.sh</em></span> to:
+ </p><pre class="programlisting">
+ (conntrack-tools-x.x.x)# cp doc/sync/primary-backup.sh /etc/conntrackd/
+</pre><p>The HA manager invokes this script when a transition happens, ie. If
+ a stateful firewall replica:</p><div class="itemizedlist"><ul type="disc"><li><p>becomes active to recover the filtering.</p></li><li><p>becomes backup.</p></li><li><p>hits failure (this is available if the HA manager has a failure state, which is true for <a href="http://www.keepalived.org" target="_top">keepalived</a>.</p></li></ul></div><p>The script is simple, and it contains the different actions that
+ <span class="emphasis"><em>conntrackd</em></span> performs to recover the filtering or
+ purge obsolete entries from the state table, among others. The script is
+ commented, you can have a look at it if you need further information.</p></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="sync-aa"></a>Active-Active setup</h3></div></div></div><p>The Active-Active setup consists of having more than one stateful
+ firewall replicas actively filtering traffic. Thus, we reduce the resource
+ waste that implies to have a backup firewall which does nothing.</p><p>We can classify the type of Active-Active setups in several
+ families:</p><div class="itemizedlist"><ul type="disc"><li><p><span class="emphasis"><em>Symmetric path routing</em></span>: The stateful firewall
+ replicas share the workload in terms of flows, ie. the packets that are
+ part of a flow are always filtered by the same firewall.</p></li><li><p><span class="emphasis"><em>Asymmetric multi-path routing</em></span>: The packets that
+ are part of a flow can be filtered by whatever stateful firewall in the
+ cluster. Thus, every flow-states have to be propagated to all the firewalls
+ in the cluster as we do not know which one would be the next to filter a
+ packet. This setup goes against the design of stateful firewalls as we
+ define the filtering policy based on flows, not in packets anymore.
+ </p></li></ul></div><p>As for 0.9.8, the design of <span class="emphasis"><em>conntrackd</em></span> allows you
+ to deploy an symmetric Active-Active setup based on a static approach.
+ For example, assume that you have two virtual IPs, vIP1 and vIP2, and two
+ firewall replicas, FW1 and FW2. You can give the virtual vIP1 to the
+ firewall FW1 and the vIP2 to the FW2.
+ </p><p>Unfortunately, you will have to wait for the support for the
+ Active-Active setup based on dynamic approach, ie. a workload sharing setup
+ without directors that allow the stateful firewall share the filtering.</p><p>On the other hand, the asymmetric scenario may work if your setup
+ fulfills several strong assumptions. However, in the opinion of the author
+ of this work, the asymmetric setup goes against the design of stateful
+ firewalls and <span class="emphasis"><em>conntrackd</em></span>. Therefore, you have two
+ choices here: you can deploy an Active-Backup setup or go back to your
+ old stateless rule-set (in that case, the conntrack-tools will not be
+ of any help anymore, of course).</p></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="sync-launch"></a>Launching conntrackd</h3></div></div></div><p>
+ Once you have configured <span class="emphasis"><em>conntrackd</em></span>, you can run in
+ <span class="emphasis"><em>console mode</em></span> which is an interactive mode, in that case
+ type 'conntrackd' as root.</p><pre class="programlisting">(root)# conntrackd</pre><p>If you want to run <span class="emphasis"><em>conntrackd</em></span> in <span class="emphasis"><em>daemon
+ mode</em></span>, then type:</p><pre class="programlisting">(root)# conntrackd -d</pre><p>You can verify that conntrackd is running by checking the log messages
+ via <span class="emphasis"><em>ps</em></span>. Moreover, if <span class="emphasis"><em>conntrackd</em></span> is
+ running fine, you can dump the current status of the daemon:</p><pre class="programlisting">
+ # conntrackd -s
+ cache internal:
+ current active connections: 4
+ connections created: 4 failed: 0
+ connections updated: 0 failed: 0
+ connections destroyed: 0 failed: 0
+
+ cache external:
+ current active connections: 0
+ connections created: 0 failed: 0
+ connections updated: 0 failed: 0
+ connections destroyed: 0 failed: 0
+
+ traffic processed:
+ 0 Bytes 0 Pckts
+
+ multicast traffic:
+ 352 Bytes sent 0 Bytes recv
+ 22 Pckts sent 0 Pckts recv
+ 0 Error send 0 Error recv
+
+ multicast sequence tracking:
+ 0 Pckts mfrm 0 Pckts lost
+ </pre><p>This command displays the number of entries in the internal and
+ external cache:</p><div class="itemizedlist"><ul type="disc"><li><p>The internal cache contains the states that this firewall replica is filtering, ie. this is a cache of the kernel state table.
+ </p></li><li><p>The external cache contains the states that the other firewall replica is filtering.
+ </p></li></ul></div><p>You can dump the internal cache with the following command:</p><pre class="programlisting">
+ # conntrackd -i
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=139.174.175.20 sport=58491 dport=993 src=139.174.175.20 dst=192.168.2.100 sport=993 dport=58491 [ASSURED] mark=0 secmark=0 [active since 536s]
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=38211 dport=993 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=38211 [ASSURED] mark=0 secmark=0 [active since 536s]
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=38209 dport=993 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=38209 [ASSURED] mark=0 secmark=0 [active since 536s]
+ tcp 6 TIME_WAIT src=192.168.2.100 dst=74.125.45.166 sport=42593 dport=80 src=74.125.45.166 dst=192.168.2.100 sport=80 dport=42593 [ASSURED] [active since 165s]
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=139.174.175.20 sport=37962 dport=993 src=139.174.175.20 dst=192.168.2.100 sport=993 dport=37962 [ASSURED] mark=0 secmark=0 [active since 536s]
+ </pre><p>You can dump the external cache with the following command:</p><pre class="programlisting"># conntrackd -e</pre><p>If the replication works fine, <span class="emphasis"><em>conntrackd -s</em></span>
+ displays the active's internal cache should display the same number of
+ entries than the backup's external cache and vice-versa.</p><p>To verify that the recovery works fine, if you trigger a fail-over,
+ the log files should display the following information:</p><pre class="programlisting">
+ [Thu Sep 18 18:03:02 2008] (pid=9759) [notice] committing external cache
+ [Thu Sep 18 18:03:02 2008] (pid=9759) [notice] Committed 1545 new entries</pre><p>This means that the state entries have been injected into the kernel correctly.</p></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="sync-trouble"></a>Troubleshooting</h3></div></div></div><p>Problems with <span class="emphasis"><em>conntrackd</em></span>? The following list
+ of questions should help for troubleshooting:</p><div class="qandaset"><dl><dt>1. <a href="#id2553370">
+ I see packets lost in conntrackd -s
+ </a></dt><dt>2. <a href="#id2553403">
+ The log messages report that the maximum netlink socket buffer has been reached.
+ </a></dt><dt>3. <a href="#id2553432">
+ I see can't open multicast server in the log messages
+ </a></dt><dt>4. <a href="#id2602252">
+ Can I use wackamole, heartattack or any other HA manager?
+ </a></dt></dl><table border="0" summary="Q and A Set"><col align="left" width="1%" /><tbody><tr class="question"><td align="left" valign="top"><a id="id2553370"></a><a id="id2553372"></a><b>1.</b></td><td align="left" valign="top"><p>
+ I see <span class="emphasis"><em>packets lost</em></span> in <span class="emphasis"><em>conntrackd -s</em></span>
+ </p></td></tr><tr class="answer"><td align="left" valign="top"></td><td align="left" valign="top"><p>
+ You can rise the value of <span class="emphasis"><em>McastRcvSocketBuffer</em></span> and <span class="emphasis"><em>McastRcvSocketBuffer</em></span>, if the problem is due to buffer overruns in the multicast sender or the receiver, the problem should disapear.
+ </p></td></tr><tr class="question"><td align="left" valign="top"><a id="id2553403"></a><a id="id2553405"></a><b>2.</b></td><td align="left" valign="top"><p>
+ The log messages report that the <span class="emphasis"><em>maximum netlink socket buffer has been reached</em></span>.
+ </p></td></tr><tr class="answer"><td align="left" valign="top"></td><td align="left" valign="top"><p>
+ You can increase the values of <span class="emphasis"><em>SocketBufferSize</em></span> and <span class="emphasis"><em>SocketBufferSizeMaxGrown</em></span>.
+ </p></td></tr><tr class="question"><td align="left" valign="top"><a id="id2553432"></a><a id="id2553435"></a><b>3.</b></td><td align="left" valign="top"><p>
+ I see <span class="emphasis"><em>can't open multicast server</em></span> in the log messages
+ </p></td></tr><tr class="answer"><td align="left" valign="top"></td><td align="left" valign="top"><p>
+ Make sure that the <span class="emphasis"><em>IPv4_interface</em></span> clause has the IP of the dedicated link.
+ </p></td></tr><tr class="question"><td align="left" valign="top"><a id="id2602252"></a><a id="id2602254"></a><b>4.</b></td><td align="left" valign="top"><p>
+ Can I use <a href="http://www.backhand.org/wackamole/" target="_top">wackamole</a>, heartattack or any other HA manager?
+ </p></td></tr><tr class="answer"><td align="left" valign="top"></td><td align="left" valign="top"><p>
+ Absolutely, you can. But before reporting issues, make sure that your HA manager is not the source of the problems.
+ </p></td></tr></tbody></table></div></div></div></div></div></body></html>
diff --git a/doc/manual/conntrack-tools.tmpl b/doc/manual/conntrack-tools.tmpl
new file mode 100644
index 0000000..b897318
--- /dev/null
+++ b/doc/manual/conntrack-tools.tmpl
@@ -0,0 +1,577 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
+
+<book id="conntrack-tools-how-to">
+ <bookinfo>
+ <title>The conntrack-tools user manual</title>
+
+ <authorgroup>
+ <author>
+ <firstname>Pablo</firstname>
+ <surname>Neira Ayuso</surname>
+ <affiliation>
+ <address>
+ <email>pablo@netfilter.org</email>
+ </address>
+ </affiliation>
+ </author>
+ </authorgroup>
+
+ <copyright>
+ <year>2008</year>
+ <holder>Pablo Neira Ayuso</holder>
+ </copyright>
+
+ <legalnotice>
+ <para>
+ Permission is granted to copy, distribute and/or modify this document
+ under the terms of the GNU Free Documentation License, Version 1.2
+ or any later version published by the Free Software Foundation;
+ with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+ A copy of the license is included in the section entitled "GNU
+ Free Documentation License".
+ </para>
+ </legalnotice>
+
+ <releaseinfo>
+ This document details how to install and configure the
+ <ulink url="http://conntrack-tools.netfilter.org">conntrack-tools</ulink>
+ 0.9.8. This software is under development, for that reason, it is likely
+ that this document will evolve in the future to cover new features and
+ changes.</releaseinfo>
+
+ </bookinfo>
+
+ <toc></toc>
+
+ <chapter id="introduction"><title>Introduction</title>
+
+ <para>This document should be a kick-off point to install and configure the
+ <ulink url="http://conntrack-tools.netfilter.org">conntrack-tools</ulink>.
+ If you find any error or imprecision in this document, please send an email
+ to the author, it will be appreciated.</para>
+
+ <para>In this document, the author assumes that the reader is familiar with firewalling concepts and iptables in general. If this is not your case, I suggest you to read the iptables documentation before going ahead. Moreover, the reader must also understand the difference between <emphasis>stateful</emphasis> and <emphasis>stateless</emphasis> firewalls. If this is not your case, I strongly suggest you to read the article <ulink url="http://people.netfilter.org/pablo/docs/login.pdf">Netfilter's Connection Tracking System</ulink> published in <emphasis>:login; the USENIX magazine</emphasis>. That document contains a general description that should help to clarify the concepts.</para>
+
+<para>If you do not fulfill the previous requirements, this documentation is likely to be a source of frustration. Probably, you wonder why I'm insisting on these prerequisites too much, the fact is that if your iptables rule-set is <emphasis>stateless</emphasis>, it is very likely that the <emphasis>conntrack-tools</emphasis> will not be of any help for you. You have been warned!</para>
+
+ </chapter>
+ <chapter id="what"><title>What are the conntrack-tools?</title>
+
+ <para>The conntrack-tools are a set of free software tools for GNU/Linux that allow system administrators interact, from user-space, with the in-kernel <ulink url="http://people.netfilter.org/pablo/docs/login.pdf">Connection Tracking System</ulink>, which is the module that enables stateful packet inspection for iptables. Probably, you did not hear about this module so far. However, if any of the rules of your rule-set use the <emphasis>state</emphasis> or <emphasis>ctstate</emphasis> iptables matches, you are indeed using it.
+
+ </para>
+
+<para>The <ulink url="http://conntrack-tools.netfilter.org">conntrack-tools</ulink> package contains two programs:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para><emphasis>conntrack</emphasis> is command line interface conntrack provides a more flexible interface to the connnection tracking system than /proc/net/ip_conntrack. With conntrack, you can show, delete and update the existing state entries; and you can also listen to flow events.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis>conntrackd</emphasis> is the user-space connection tracking daemon. This daemon can be used to deploy fault-tolerant GNU/Linux firewalls but you can also use it to collect flow-based statistics of the firewall use.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>Although the name of both tools is very similar - and you can blame me for that, I'm not a marketing guy - they are used for very different tasks.</para>
+
+ </chapter>
+
+ <chapter id="requirements"><title>Requirements</title>
+
+ <para>You have to install the following software in order to get the <emphasis>conntrack-tools</emphasis> working. Make sure that you have installed them correctly before going ahead:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para><ulink url="http://www.kernel.org">Linux kernel</ulink> version &gt;= 2.6.18 that, at least, has support for:</para>
+ <itemizedlist>
+ <listitem>
+ <para>Connection Tracking System.</para>
+ <itemizedlist>
+ <listitem>
+ <para>CONFIG_NF_CONNTRACK=m</para>
+ </listitem>
+ <listitem>
+ <para>CONFIG_NF_CONNTRACK_IPV4=m</para>
+ </listitem>
+ <listitem>
+ <para>CONFIG_NF_CONNTRACK_IPV6=m (if your setup supports IPv6)</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+ <listitem>
+ <para>nfnetlink: the generic messaging interface for Netfilter.</para>
+ <itemizedlist>
+ <listitem>
+ <para>CONFIG_NETFILTER_NETLINK=m</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+ <listitem>
+ <para>nf_conntrack_netlink: the messaging interface for the Connection Tracking System.</para>
+ <itemizedlist>
+ <listitem>
+ <para>CONFIG_NF_CT_NETLINK=m</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+ <listitem>
+ <para>connection tracking event notification API: the flow-based event notification interface.</para>
+ <itemizedlist>
+ <listitem>
+ <para>CONFIG_NF_CONNTRACK_EVENTS=y</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+ </itemizedlist>
+ <note><title>Verifying kernel support</title>
+ <para>
+ Make sure you have loaded <emphasis>nf_conntrack</emphasis>, <emphasis>nf_conntrack_ipv4</emphasis> (if your setup also supports IPv6, <emphasis>nf_conntrack_ipv6</emphasis>) and <emphasis>nf_conntrack_netlink</emphasis>.
+ </para>
+ </note>
+ </listitem>
+ <listitem>
+ <para>libnfnetlink: the netfilter netlink library use the official release available in <ulink url="http://www.netfilter.org">netfilter.org</ulink></para>
+ </listitem>
+ <listitem>
+ <para>libnetfilter_conntrack: the netfilter netlink library use the official release available in <ulink url="http://www.netfilter.org">netfilter.org</ulink></para>
+ </listitem>
+ </itemizedlist>
+ </chapter>
+
+ <chapter id="Installation"><title>Installation</title>
+
+ <para>To compile and install the <emphasis>conntrack-tools</emphasis> run the following commands:</para>
+ <programlisting>
+ (non-root)$ tar xvjf conntrack-tools-x.x.x.tar.bz2
+ (non-root)$ cd conntrack-tools-x.x.x
+ (non-root)$ ./configure --prefix=/usr
+ (non-root)$ make
+ (root) # make install</programlisting>
+
+<note><title>Fedora Users</title>
+ <para>If you are installing the libraries in /usr/local/, do not forget to do the following things:</para>
+ <itemizedlist>
+ <listitem><para>PKG_CONFIG_PATH=/usr/local/lib/pkgconfig; export PKG_CONFIG_PATH</para></listitem>
+ <listitem><para>Add `/usr/local/lib' to your /etc/ld.so.conf file and run `ldconfig'</para></listitem>
+ </itemizedlist>
+ <para>Check `ldd' for trouble-shooting, read <ulink url="http://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html">this</ulink> for more information on how libraries work.</para>
+</note>
+
+<note><title>Verifying kernel support</title>
+ <para>To check that the modules are enabled in the kernel, run <emphasis>`conntrack -E'</emphasis> and generate traffic, you should see flow events reporting new connections and updates.
+ </para>
+</note>
+
+ </chapter>
+
+ <chapter id="conntrack"><title>Using conntrack: the command line interface</title>
+
+ <para>The <emphasis>/proc/net/ip_conntrack</emphasis> interface is very limited as it only allows you to display the existing flows, their state and other information:</para>
+
+ <programlisting>
+ # cat /proc/net/ip_conntrack
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=0 secmark=0 use=1
+ tcp 6 431698 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34849 dport=993 packets=244 bytes=18723 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34849 packets=203 bytes=144731 [ASSURED] mark=0 secmark=0 use=1
+ </programlisting>
+
+<para>The command line tool <emphasis>conntrack</emphasis> can be used to display the same information:</para>
+ <programlisting>
+ # conntrack -L
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=0 secmark=0 use=1
+ tcp 6 431698 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34849 dport=993 packets=244 bytes=18723 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34849 packets=203 bytes=144731 [ASSURED] mark=0 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 2 flow entries have been shown.
+ </programlisting>
+
+<para>You can natively filter the output without using <emphasis>grep</emphasis>:</para>
+<programlisting>
+ # conntrack -L -p tcp --dport 34856
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=0 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 1 flow entries have been shown.
+ </programlisting>
+
+<para>Update the mark based on a selection, this allows you to change the mark of an entry without using the CONNMARK target:</para>
+<programlisting>
+ # conntrack -U -p tcp --dport 3486 --mark 10
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=1 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 1 flow entries has been updated.
+ </programlisting>
+
+<para>Delete one entry, this can be used to block traffic (you have to set <emphasis>/proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_be_liberal</emphasis> to zero).</para>
+<programlisting>
+ # conntrack -D -p tcp --dport 3486
+ tcp 6 431982 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=34846 dport=993 packets=169 bytes=14322 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=34846 packets=113 bytes=34787 [ASSURED] mark=1 secmark=0 use=1
+conntrack v0.9.7 (conntrack-tools): 1 flow entries has been deleted.
+ </programlisting>
+
+<para>Display the connection tracking events:</para>
+<programlisting>
+ # conntrack -E
+ [NEW] udp 17 30 src=192.168.2.100 dst=192.168.2.1 sport=57767 dport=53 [UNREPLIED] src=192.168.2.1 dst=192.168.2.100 sport=53 dport=57767
+ [UPDATE] udp 17 29 src=192.168.2.100 dst=192.168.2.1 sport=57767 dport=53 src=192.168.2.1 dst=192.168.2.100 sport=53 dport=57767
+ [NEW] tcp 6 120 SYN_SENT src=192.168.2.100 dst=66.102.9.104 sport=33379 dport=80 [UNREPLIED] src=66.102.9.104 dst=192.168.2.100 sport=80 dport=33379
+ [UPDATE] tcp 6 60 SYN_RECV src=192.168.2.100 dst=66.102.9.104 sport=33379 dport=80 src=66.102.9.104 dst=192.168.2.100 sport=80 dport=33379
+ [UPDATE] tcp 6 432000 ESTABLISHED src=192.168.2.100 dst=66.102.9.104 sport=33379 dport=80 src=66.102.9.104 dst=192.168.2.100 sport=80 dport=33379 [ASSURED]
+</programlisting>
+
+<para>You can also display the existing flows in XML format, filter the output based on the NAT handling applied, etc.</para>
+
+</chapter>
+
+ <chapter id="settingup"><title>Setting up conntrackd: the daemon</title>
+
+ <para>The daemon <emphasis>conntrackd</emphasis> supports two working modes:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para><emphasis>State table synchronization</emphasis>: the daemon can be used to synchronize the connection tracking state table between several firewall replicas. This can be used to deploy fault-tolerant stateful firewalls. This is the main feature of the daemon.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis>Flow-based statistics collection</emphasis>: the daemon can be used to collect flow-based statistics. This feature is similar to what <ulink url="http://www.netfilter.org/projects/ulogd/">ulogd-2.x</ulink> provides.</para>
+ </listitem>
+ </itemizedlist>
+
+ <sect1 id="sync"><title>State table synchronization</title>
+
+ <sect2 id="sync-requirements"><title>Requirements</title>
+
+ <para>In order to get <emphasis>conntrackd</emphasis> working in synchronization mode, you have to fulfill the following requirements:</para>
+
+ <orderedlist>
+ <listitem>
+ <para>A <emphasis>high availability manager</emphasis> like <ulink url="http://www.keepalived.org">keepalived</ulink> that manages the virtual IPs of the
+ firewall cluster, detects errors, and decide when to migrate the virtual IPs
+ from one firewall replica to another. Without it, <emphasis>conntrackd</emphasis> will not work appropriately.</para>
+
+ <para>The state synchronization setup requires a working installation of <ulink url="http://www.keepalived.org">keepalived</ulink>, preferibly a recent version. Check if your distribution comes with a recent packaged version. Otherwise, you may compile it from the sources.
+ </para>
+
+ <para>
+ There is a very simple example file in the <emphasis>conntrackd</emphasis>
+ sources to setup a simple HA cluster with keepalived (see the file
+ keepalived.conf under the doc/sync/ directory). This file can be used to
+ set up a simple VRRP cluster composed of two machines that hold the virtual
+ IPs 192.168.0.100 on eth0 and 192.168.1.100 on eth1.</para>
+
+ <para>If you are not familiar with <emphasis>keepalived</emphasis>, please
+ read the official documentation available at the keepalived website
+ (<ulink url="http://www.keepalived.org">http://www.keepalived.org</ulink>).</para>
+
+<para>If you use a different high availability manager, make sure it works correctly before going ahead.</para>
+
+ </listitem>
+
+ <listitem>
+ <para>A dedicated link. The dedicated link between the firewalls is used
+ to transmit and receive the state information. The use of a dedicated link
+ is mandatory for security reasons as someone may pick the state information
+ that is transfered between the firewalls.</para>
+ </listitem>
+
+ <listitem>
+ <para>A well-formed stateful rule-set. Otherwise you are likely to experience
+ problems during the fail-over. An example of a well-formed stateful iptables
+ rule-set is available in the <ulink url="http://conntrack-tools.netfilter.org/testcase.html">conntrack-tools website</ulink>.</para>
+ </listitem>
+
+ <listitem>
+ <para>If your Linux kernel is &lt; 2.6.22, you have to disable TCP window
+ tracking:
+ <programlisting>
+ # echo 1 > /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_be_liberal
+ </programlisting>
+ </para>
+ </listitem>
+
+ </orderedlist>
+
+ </sect2>
+
+ <sect2 id="sync-configure"><title>Configuring the daemon</title>
+
+ <para>The daemon <emphasis>conntrackd</emphasis> in synchronization mode
+ supports up to three replication approaches:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para><emphasis>notrack</emphasis>: this approach is the most simple as
+ it is based on a best effort replication protocol, ie. unreliable
+ protocol. This protocol sends and receives the state information
+ without performing any specific checking.
+ </para>
+ </listitem>
+ <listitem>
+ <para><emphasis>ft-fw</emphasis>: this approach is based on a reliable
+ protocol that performs message tracking. Thus, the protocol can recover
+ from message loss, re-ordering and corruption.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis>alarm</emphasis>: this approach is spamming. It is based
+ on a alarm-based protocol that periodically re-sends the flow state to
+ the backup firewall replicas. This protocol consumes a lot of bandwidth
+ but it resolves synchronization problems fast.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>The three existing approaches are soft real-time asynchronous
+ replication protocols that are aimed to have negligible impact in terms
+ of latency and bandwidth throughput in the stateful firewall filtering.</para>
+
+ <para>To configure <emphasis>conntrackd</emphasis> in any of the existing
+ synchronization modes, you have to copy the example configuration file to
+ the directory /etc/conntrackd/ on every firewall replica. Note that
+ <emphasis>_type_</emphasis> is the synchronization type selected.</para>
+
+<programlisting>
+ (conntrack-tools-x.x.x)# cp doc/_type_/conntrackd.conf /etc/conntrackd/conntrackd.conf
+</programlisting>
+
+<para>
+ Do not forget to edit the files before going ahead. There are several
+ parameters that you have to tune to adapt the example configuration file
+ to your setup.
+</para>
+
+<note><title>Configuration file location</title>
+ <para>If you don't want to put the config file under /etc/conntrackd/, just tell conntrackd where to find it passing the option -C.</para>
+</note>
+
+</sect2>
+
+<sect2 id="sync-pb"><title>Active-Backup setup</title>
+
+ <para>In the Active-Backup setup, one of the stateful firewall replicas
+ filters traffic and the other acts as backup. If you use this approach,
+ you have to copy the script <emphasis>primary-backup.sh</emphasis> to:
+ </para>
+
+<programlisting>
+ (conntrack-tools-x.x.x)# cp doc/sync/primary-backup.sh /etc/conntrackd/
+</programlisting>
+
+ <para>The HA manager invokes this script when a transition happens, ie. If
+ a stateful firewall replica:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>becomes active to recover the filtering.</para>
+ </listitem>
+ <listitem>
+ <para>becomes backup.</para>
+ </listitem>
+ <listitem>
+ <para>hits failure (this is available if the HA manager has a failure state, which is true for <ulink url="http://www.keepalived.org">keepalived</ulink>.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>The script is simple, and it contains the different actions that
+ <emphasis>conntrackd</emphasis> performs to recover the filtering or
+ purge obsolete entries from the state table, among others. The script is
+ commented, you can have a look at it if you need further information.</para>
+
+</sect2>
+
+<sect2 id="sync-aa"><title>Active-Active setup</title>
+
+ <para>The Active-Active setup consists of having more than one stateful
+ firewall replicas actively filtering traffic. Thus, we reduce the resource
+ waste that implies to have a backup firewall which does nothing.</para>
+
+ <para>We can classify the type of Active-Active setups in several
+ families:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para><emphasis>Symmetric path routing</emphasis>: The stateful firewall
+ replicas share the workload in terms of flows, ie. the packets that are
+ part of a flow are always filtered by the same firewall.</para>
+ </listitem>
+ <listitem>
+ <para><emphasis>Asymmetric multi-path routing</emphasis>: The packets that
+ are part of a flow can be filtered by whatever stateful firewall in the
+ cluster. Thus, every flow-states have to be propagated to all the firewalls
+ in the cluster as we do not know which one would be the next to filter a
+ packet. This setup goes against the design of stateful firewalls as we
+ define the filtering policy based on flows, not in packets anymore.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>As for 0.9.8, the design of <emphasis>conntrackd</emphasis> allows you
+ to deploy an symmetric Active-Active setup based on a static approach.
+ For example, assume that you have two virtual IPs, vIP1 and vIP2, and two
+ firewall replicas, FW1 and FW2. You can give the virtual vIP1 to the
+ firewall FW1 and the vIP2 to the FW2.
+ </para>
+
+ <para>Unfortunately, you will have to wait for the support for the
+ Active-Active setup based on dynamic approach, ie. a workload sharing setup
+ without directors that allow the stateful firewall share the filtering.</para>
+
+ <para>On the other hand, the asymmetric scenario may work if your setup
+ fulfills several strong assumptions. However, in the opinion of the author
+ of this work, the asymmetric setup goes against the design of stateful
+ firewalls and <emphasis>conntrackd</emphasis>. Therefore, you have two
+ choices here: you can deploy an Active-Backup setup or go back to your
+ old stateless rule-set (in that case, the conntrack-tools will not be
+ of any help anymore, of course).</para>
+
+</sect2>
+
+<sect2 id="sync-launch"><title>Launching conntrackd</title>
+
+ <para>
+ Once you have configured <emphasis>conntrackd</emphasis>, you can run in
+ <emphasis>console mode</emphasis> which is an interactive mode, in that case
+ type 'conntrackd' as root.</para>
+
+ <programlisting>(root)# conntrackd</programlisting>
+
+ <para>If you want to run <emphasis>conntrackd</emphasis> in <emphasis>daemon
+ mode</emphasis>, then type:</para>
+
+ <programlisting>(root)# conntrackd -d</programlisting>
+
+ <para>You can verify that conntrackd is running by checking the log messages
+ via <emphasis>ps</emphasis>. Moreover, if <emphasis>conntrackd</emphasis> is
+ running fine, you can dump the current status of the daemon:</para>
+
+ <programlisting>
+ # conntrackd -s
+ cache internal:
+ current active connections: 4
+ connections created: 4 failed: 0
+ connections updated: 0 failed: 0
+ connections destroyed: 0 failed: 0
+
+ cache external:
+ current active connections: 0
+ connections created: 0 failed: 0
+ connections updated: 0 failed: 0
+ connections destroyed: 0 failed: 0
+
+ traffic processed:
+ 0 Bytes 0 Pckts
+
+ multicast traffic:
+ 352 Bytes sent 0 Bytes recv
+ 22 Pckts sent 0 Pckts recv
+ 0 Error send 0 Error recv
+
+ multicast sequence tracking:
+ 0 Pckts mfrm 0 Pckts lost
+ </programlisting>
+
+ <para>This command displays the number of entries in the internal and
+ external cache:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>The internal cache contains the states that this firewall replica is filtering, ie. this is a cache of the kernel state table.
+ </para>
+ </listitem>
+ <listitem>
+ <para>The external cache contains the states that the other firewall replica is filtering.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>You can dump the internal cache with the following command:</para>
+
+ <programlisting>
+ # conntrackd -i
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=139.174.175.20 sport=58491 dport=993 src=139.174.175.20 dst=192.168.2.100 sport=993 dport=58491 [ASSURED] mark=0 secmark=0 [active since 536s]
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=38211 dport=993 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=38211 [ASSURED] mark=0 secmark=0 [active since 536s]
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=123.59.27.117 sport=38209 dport=993 src=123.59.27.117 dst=192.168.2.100 sport=993 dport=38209 [ASSURED] mark=0 secmark=0 [active since 536s]
+ tcp 6 TIME_WAIT src=192.168.2.100 dst=74.125.45.166 sport=42593 dport=80 src=74.125.45.166 dst=192.168.2.100 sport=80 dport=42593 [ASSURED] [active since 165s]
+ tcp 6 ESTABLISHED src=192.168.2.100 dst=139.174.175.20 sport=37962 dport=993 src=139.174.175.20 dst=192.168.2.100 sport=993 dport=37962 [ASSURED] mark=0 secmark=0 [active since 536s]
+ </programlisting>
+
+ <para>You can dump the external cache with the following command:</para>
+
+ <programlisting># conntrackd -e</programlisting>
+
+ <para>If the replication works fine, <emphasis>conntrackd -s</emphasis>
+ displays the active's internal cache should display the same number of
+ entries than the backup's external cache and vice-versa.</para>
+
+ <para>To verify that the recovery works fine, if you trigger a fail-over,
+ the log files should display the following information:</para>
+
+ <programlisting>
+ [Thu Sep 18 18:03:02 2008] (pid=9759) [notice] committing external cache
+ [Thu Sep 18 18:03:02 2008] (pid=9759) [notice] Committed 1545 new entries</programlisting>
+
+ <para>This means that the state entries have been injected into the kernel correctly.</para>
+
+</sect2>
+
+<sect2 id="sync-trouble"><title>Troubleshooting</title>
+
+ <para>Problems with <emphasis>conntrackd</emphasis>? The following list
+ of questions should help for troubleshooting:</para>
+
+ <qandaset>
+
+ <qandaentry>
+ <question>
+ <para>
+ I see <emphasis>packets lost</emphasis> in <emphasis>conntrackd -s</emphasis>
+ </para>
+ </question>
+ <answer>
+ <para>
+ You can rise the value of <emphasis>McastRcvSocketBuffer</emphasis> and <emphasis>McastRcvSocketBuffer</emphasis>, if the problem is due to buffer overruns in the multicast sender or the receiver, the problem should disapear.
+ </para>
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+ <para>
+ The log messages report that the <emphasis>maximum netlink socket buffer has been reached</emphasis>.
+ </para>
+ </question>
+ <answer>
+ <para>
+ You can increase the values of <emphasis>SocketBufferSize</emphasis> and <emphasis>SocketBufferSizeMaxGrown</emphasis>.
+ </para>
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+ <para>
+ I see <emphasis>can't open multicast server</emphasis> in the log messages
+ </para>
+ </question>
+ <answer>
+ <para>
+ Make sure that the <emphasis>IPv4_interface</emphasis> clause has the IP of the dedicated link.
+ </para>
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+ <para>
+ Can I use <ulink url="http://www.backhand.org/wackamole/">wackamole</ulink>, heartattack or any other HA manager?
+ </para>
+ </question>
+ <answer>
+ <para>
+ Absolutely, you can. But before reporting issues, make sure that your HA manager is not the source of the problems.
+ </para>
+ </answer>
+ </qandaentry>
+
+ </qandaset>
+
+</sect2>
+
+</sect1>
+
+</chapter>
+
+</book>
diff --git a/doc/manual/docbook.css b/doc/manual/docbook.css
new file mode 100644
index 0000000..81f4016
--- /dev/null
+++ b/doc/manual/docbook.css
@@ -0,0 +1,43 @@
+/* stolen from "Making your DocBook/XML HTML output not suck" */
+
+body {
+ font-family: luxi sans,sans-serif;
+}
+
+.screen {
+ font-family: monospace;
+ font-size: 1em;
+ display: block;
+ padding: 10px;
+ border: 1px solid #bbb;
+ background-color: #eee;
+ color: #000;
+ overflow: auto;
+ border-radius: 2.5px;
+ -moz-border-radius: 2.5px;
+ margin: 0.5em 2em;
+}
+
+.programlisting {
+ font-family: monospace;
+ font-size: 1em;
+ display: block;
+ padding: 10px;
+ border: 1px solid #bbb;
+ background-color: #ddd;
+ color: #000;
+ overflow: auto;
+ border-radius: 2.5px;
+ -moz-border-radius: 2.5px;
+ margin: 0.5em 2em;
+}
+
+a {
+ text-decoration: none;
+ border-bottom: 1px dotted #000;
+}
+
+a:hover {
+ background-color: #777;
+ color: #fff;
+}
diff --git a/doc/stats/conntrackd.conf b/doc/stats/conntrackd.conf
new file mode 100644
index 0000000..0941f64
--- /dev/null
+++ b/doc/stats/conntrackd.conf
@@ -0,0 +1,140 @@
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon. This value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # negative value reduces the chances to lose state-change events.
+ # Default is 0. See man nice(1) for more information.
+ #
+ Nice -1
+
+ #
+ # Select a different scheduler for the daemon, you can select between
+ # RR and FIFO and the process priority (minimum is 0, maximum is 99).
+ # See man sched_setscheduler(2) for more information. Using a RT
+ # scheduler reduces the chances to overrun the Netlink buffer.
+ #
+ # Scheduler {
+ # Type FIFO
+ # Priority 99
+ # }
+
+ #
+ # Number of buckets in the caches: hash table
+ #
+ HashSize 8192
+
+ #
+ # Maximum number of conntracks:
+ # it must be >= $ cat /proc/sys/net/ipv4/netfilter/ip_conntrack_max
+ #
+ HashLimit 65535
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ #LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink socket buffer size
+ #
+ NetlinkBufferSize 262142
+
+ #
+ # Increase the socket buffer up to maximun if required
+ #
+ NetlinkBufferSizeMaxGrowth 655355
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ #
+ Filter {
+ #
+ # Accept only certain protocols: You may want to log the
+ # state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ # IPv6_address ::1
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # The existing TCP states are: SYN_SENT, SYN_RECV, ESTABLISHED,
+ # FIN_WAIT, CLOSE_WAIT, LAST_ACK, TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
+
+Stats {
+ #
+ # If you enable this option, the daemon writes the information about
+ # destroyed connections to a logfile. Default is off.
+ # Logfile: on, off, or a filename
+ # Default file: (/var/log/conntrackd-stats.log)
+ #
+ LogFile on
+
+ # If you want reliable event reporting over Netlink, set on this
+ # option. If you set on this clause, it is a good idea to set off
+ # NetlinkOverrunResync. This option is off by default and you need
+ # a Linux kernel >= 2.6.31.
+ #
+ # NetlinkEventsReliable Off
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # Enable connection logging via Syslog. Default is off.
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # If you set the facility, use the same as in the General clause,
+ # otherwise you'll get a warning message.
+ #
+ #Syslog on
+}
diff --git a/doc/stats/conntrackd.conf.orig b/doc/stats/conntrackd.conf.orig
new file mode 100644
index 0000000..1f1a697
--- /dev/null
+++ b/doc/stats/conntrackd.conf.orig
@@ -0,0 +1,121 @@
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon. This value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # negative value reduces the chances to lose state-change events.
+ # Default is 0. See man nice(1) for more information.
+ #
+ Nice -1
+
+ #
+ # Number of buckets in the caches: hash table
+ #
+ HashSize 8192
+
+ #
+ # Maximum number of conntracks:
+ # it must be >= $ cat /proc/sys/net/ipv4/netfilter/ip_conntrack_max
+ #
+ HashLimit 65535
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ #LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink socket buffer size
+ #
+ NetlinkBufferSize 262142
+
+ #
+ # Increase the socket buffer up to maximun if required
+ #
+ NetlinkBufferSizeMaxGrowth 655355
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ #
+ Filter {
+ #
+ # Accept only certain protocols: You may want to log the
+ # state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # The existing TCP states are: SYN_SENT, SYN_RECV, ESTABLISHED,
+ # FIN_WAIT, CLOSE_WAIT, LAST_ACK, TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
+
+Stats {
+ #
+ # If you enable this option, the daemon writes the information about
+ # destroyed connections to a logfile. Default is off.
+ # Logfile: on, off, or a filename
+ # Default file: (/var/log/conntrackd-stats.log)
+ #
+ LogFile on
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # Enable connection logging via Syslog. Default is off.
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # If you set the facility, use the same as in the General clause,
+ # otherwise you'll get a warning message.
+ #
+ #Syslog on
+}
diff --git a/doc/sync/alarm/README b/doc/sync/alarm/README
new file mode 100644
index 0000000..dfd8474
--- /dev/null
+++ b/doc/sync/alarm/README
@@ -0,0 +1 @@
+This directory contains the files for the ALARM based protocol
diff --git a/doc/sync/alarm/conntrackd.conf b/doc/sync/alarm/conntrackd.conf
new file mode 100644
index 0000000..3424e39
--- /dev/null
+++ b/doc/sync/alarm/conntrackd.conf
@@ -0,0 +1,372 @@
+#
+# Synchronizer settings
+#
+Sync {
+ Mode ALARM {
+ #
+ # If a conntrack entry is not modified in <= 15 seconds, then
+ # a message is broadcasted. This mechanism is used to
+ # resynchronize nodes that just joined the multicast group
+ #
+ RefreshTime 15
+
+ #
+ # If we don't receive a notification about the state of
+ # an entry in the external cache after N seconds, then
+ # remove it.
+ #
+ CacheTimeout 180
+
+ #
+ # This parameter allows you to set an initial fixed timeout
+ # for the committed entries when this node goes from backup
+ # to primary. This mechanism provides a way to purge entries
+ # that were not recovered appropriately after the specified
+ # fixed timeout. If you set a low value, TCP entries in
+ # Established states with no traffic may hang. For example,
+ # an SSH connection without KeepAlive enabled. If not set,
+ # the daemon uses an approximate timeout value calculation
+ # mechanism. By default, this option is not set.
+ #
+ # CommitTimeout 180
+
+ #
+ # If the firewall replica goes from primary to backup,
+ # the conntrackd -t command is invoked in the script.
+ # This command schedules a flush of the table in N seconds.
+ # This is useful to purge the connection tracking table of
+ # zombie entries and avoid clashes with old entries if you
+ # trigger several consecutive hand-overs. Default is 60 seconds
+ #
+ # PurgeTimeout 60
+ }
+
+ #
+ # Multicast IP and interface where messages are
+ # broadcasted (dedicated link). IMPORTANT: Make sure
+ # that iptables accepts traffic for destination
+ # 225.0.0.50, eg:
+ #
+ # iptables -I INPUT -d 225.0.0.50 -j ACCEPT
+ # iptables -I OUTPUT -d 225.0.0.50 -j ACCEPT
+ #
+ Multicast {
+ #
+ # Multicast address: The address that you use as destination
+ # in the synchronization messages. You do not have to add
+ # this IP to any of your existing interfaces. If any doubt,
+ # do not modify this value.
+ #
+ IPv4_address 225.0.0.50
+
+ #
+ # The multicast group that identifies the cluster. If any
+ # doubt, do not modify this value.
+ #
+ Group 3780
+
+ #
+ # IP address of the interface that you are going to use to
+ # send the synchronization messages. Remember that you must
+ # use a dedicated link for the synchronization messages.
+ #
+ IPv4_interface 192.168.100.100
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ Interface eth2
+
+ # The multicast sender uses a buffer to enqueue the packets
+ # that are going to be transmitted. The default size of this
+ # socket buffer is available at /proc/sys/net/core/wmem_default.
+ # This value determines the chances to have an overrun in the
+ # sender queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size
+ # of the sender buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ SndSocketBuffer 1249280
+
+ # The multicast receiver uses a buffer to enqueue the packets
+ # that the socket is pending to handle. The default size of this
+ # socket buffer is available at /proc/sys/net/core/rmem_default.
+ # This value determines the chances to have an overrun in the
+ # receiver queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size of
+ # the receiver buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming. This is a good
+ # property to achieve fault-tolerance. In case of doubt, do
+ # not modify this value.
+ #
+ Checksum on
+ }
+ #
+ # You can specify more than one dedicated link. Thus, if one dedicated
+ # link fails, conntrackd can fail-over to another. Note that adding
+ # more than one dedicated link does not mean that state-updates will
+ # be sent to all of them. There is only one active dedicated link at
+ # a given moment. The `Default' keyword indicates that this interface
+ # will be selected as the initial dedicated link. You can have
+ # up to 4 redundant dedicated links. Note: Use different multicast
+ # groups for every redundant link.
+ #
+ # Multicast Default {
+ # IPv4_address 225.0.0.51
+ # Group 3781
+ # IPv4_interface 192.168.100.101
+ # Interface eth3
+ # # SndSocketBuffer 1249280
+ # # RcvSocketBuffer 1249280
+ # Checksum on
+ # }
+
+ #
+ # You can use Unicast UDP instead of Multicast to propagate events.
+ # Note that you cannot use unicast UDP and Multicast at the same
+ # time, you can only select one.
+ #
+ # UDP {
+ #
+ # UDP address that this firewall uses to listen to events.
+ #
+ # IPv4_address 192.168.2.100
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_address fe80::215:58ff:fe28:5a27
+
+ #
+ # Destination UDP address that receives events, ie. the other
+ # firewall's dedicated link address.
+ #
+ # IPv4_Destination_Address 192.168.2.101
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_Destination_Address fe80::2d0:59ff:fe2a:775c
+
+ #
+ # UDP port used
+ #
+ # Port 3780
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ # Interface eth2
+
+ #
+ # The sender socket buffer size
+ #
+ # SndSocketBuffer 1249280
+
+ #
+ # The receiver socket buffer size
+ #
+ # RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming.
+ #
+ # Checksum on
+ # }
+}
+
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon, this value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # very low value reduces the chances to lose state-change events.
+ # Default is 0 but this example file sets it to most favourable
+ # scheduling as this is generally a good idea. See man nice(1) for
+ # more information.
+ #
+ Nice -20
+
+ #
+ # Select a different scheduler for the daemon, you can select between
+ # RR and FIFO and the process priority (minimum is 0, maximum is 99).
+ # See man sched_setscheduler(2) for more information. Using a RT
+ # scheduler reduces the chances to overrun the Netlink buffer.
+ #
+ # Scheduler {
+ # Type FIFO
+ # Priority 99
+ # }
+
+ #
+ # Number of buckets in the cache hashtable. The bigger it is,
+ # the closer it gets to O(1) at the cost of consuming more memory.
+ # Read some documents about tuning hashtables for further reference.
+ #
+ HashSize 32768
+
+ #
+ # Maximum number of conntracks, it should be double of:
+ # $ cat /proc/sys/net/netfilter/nf_conntrack_max
+ # since the daemon may keep some dead entries cached for possible
+ # retransmission during state synchronization.
+ #
+ HashLimit 131072
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink event socket buffer size. If you do not specify this clause,
+ # the default buffer size value in /proc/net/core/rmem_default is
+ # used. This default value is usually around 100 Kbytes which is
+ # fairly small for busy firewalls. This leads to event message dropping
+ # and high CPU consumption. This example configuration file sets the
+ # size to 2 MBytes to avoid this sort of problems.
+ #
+ NetlinkBufferSize 2097152
+
+ #
+ # The daemon doubles the size of the netlink event socket buffer size
+ # if it detects netlink event message dropping. This clause sets the
+ # maximum buffer size growth that can be reached. This example file
+ # sets the size to 8 MBytes.
+ #
+ NetlinkBufferSizeMaxGrowth 8388608
+
+ #
+ # If the daemon detects that Netlink is dropping state-change events,
+ # it automatically schedules a resynchronization against the Kernel
+ # after 30 seconds (default value). Resynchronizations are expensive
+ # in terms of CPU consumption since the daemon has to get the full
+ # kernel state-table and purge state-entries that do not exist anymore.
+ # Be careful of setting a very small value here. You have the following
+ # choices: On (enabled, use default 30 seconds value), Off (disabled)
+ # or Value (in seconds, to set a specific amount of time). If not
+ # specified, the daemon assumes that this option is enabled.
+ #
+ # NetlinkOverrunResync On
+
+ # If you want reliable event reporting over Netlink, set on this
+ # option. If you set on this clause, it is a good idea to set off
+ # NetlinkOverrunResync. This option is off by default and you need
+ # a Linux kernel >= 2.6.31.
+ #
+ # NetlinkEventsReliable Off
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # The daemon prioritizes the handling of state-change events coming
+ # from the core. With this clause, you can set the maximum number of
+ # state-change events (those coming from kernel-space) that the daemon
+ # will handle after which it will handle other events coming from the
+ # network or userspace. A low value improves interactivity (in terms of
+ # real-time behaviour) at the cost of extra CPU consumption.
+ # Default (if not set) is 100.
+ #
+ # EventIterationLimit 100
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ # You can select if conntrackd filters the event messages from
+ # user-space or kernel-space. The kernel-space event filtering
+ # saves some CPU cycles by avoiding the copy of the event message
+ # from kernel-space to user-space. The kernel-space event filtering
+ # is prefered, however, you require a Linux kernel >= 2.6.29 to
+ # filter from kernel-space. If you want to select kernel-space
+ # event filtering, use the keyword 'Kernelspace' instead of
+ # 'Userspace'.
+ #
+ Filter From Userspace {
+ #
+ # Accept only certain protocols: You may want to replicate
+ # the state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ SCTP
+ DCCP
+ # ICMP # This requires a Linux kernel >= 2.6.31
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's: Usually all the
+ # IP assigned to the firewall since local traffic must be
+ # ignored, only forwarded connections are worth to replicate.
+ # Note that these values depends on the local IPs that are
+ # assigned to the firewall.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ IPv4_address 192.168.0.100 # virtual IP 1
+ IPv4_address 192.168.1.100 # virtual IP 2
+ IPv4_address 192.168.0.1
+ IPv4_address 192.168.1.1
+ IPv4_address 192.168.100.100 # dedicated link ip
+ #
+ # You can also specify networks in format IP/cidr.
+ # IPv4_address 192.168.0.0/24
+ #
+ # You can also specify an IPv6 address
+ # IPv6_address ::1
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # This option introduces a trade-off in the replication: it
+ # reduces CPU consumption at the cost of having lazy backup
+ # firewall replicas. The existing TCP states are: SYN_SENT,
+ # SYN_RECV, ESTABLISHED, FIN_WAIT, CLOSE_WAIT, LAST_ACK,
+ # TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
diff --git a/doc/sync/alarm/conntrackd.conf.orig b/doc/sync/alarm/conntrackd.conf.orig
new file mode 100644
index 0000000..ca6e661
--- /dev/null
+++ b/doc/sync/alarm/conntrackd.conf.orig
@@ -0,0 +1,348 @@
+#
+# Synchronizer settings
+#
+Sync {
+ Mode ALARM {
+ #
+ # If a conntrack entry is not modified in <= 15 seconds, then
+ # a message is broadcasted. This mechanism is used to
+ # resynchronize nodes that just joined the multicast group
+ #
+ RefreshTime 15
+
+ #
+ # If we don't receive a notification about the state of
+ # an entry in the external cache after N seconds, then
+ # remove it.
+ #
+ CacheTimeout 180
+
+ #
+ # This parameter allows you to set an initial fixed timeout
+ # for the committed entries when this node goes from backup
+ # to primary. This mechanism provides a way to purge entries
+ # that were not recovered appropriately after the specified
+ # fixed timeout. If you set a low value, TCP entries in
+ # Established states with no traffic may hang. For example,
+ # an SSH connection without KeepAlive enabled. If not set,
+ # the daemon uses an approximate timeout value calculation
+ # mechanism. By default, this option is not set.
+ #
+ # CommitTimeout 180
+
+ #
+ # If the firewall replica goes from primary to backup,
+ # the conntrackd -t command is invoked in the script.
+ # This command schedules a flush of the table in N seconds.
+ # This is useful to purge the connection tracking table of
+ # zombie entries and avoid clashes with old entries if you
+ # trigger several consecutive hand-overs. Default is 60 seconds
+ #
+ # PurgeTimeout 60
+ }
+
+ #
+ # Multicast IP and interface where messages are
+ # broadcasted (dedicated link). IMPORTANT: Make sure
+ # that iptables accepts traffic for destination
+ # 225.0.0.50, eg:
+ #
+ # iptables -I INPUT -d 225.0.0.50 -j ACCEPT
+ # iptables -I OUTPUT -d 225.0.0.50 -j ACCEPT
+ #
+ Multicast {
+ #
+ # Multicast address: The address that you use as destination
+ # in the synchronization messages. You do not have to add
+ # this IP to any of your existing interfaces. If any doubt,
+ # do not modify this value.
+ #
+ IPv4_address 225.0.0.50
+
+ #
+ # The multicast group that identifies the cluster. If any
+ # doubt, do not modify this value.
+ #
+ Group 3780
+
+ #
+ # IP address of the interface that you are going to use to
+ # send the synchronization messages. Remember that you must
+ # use a dedicated link for the synchronization messages.
+ #
+ IPv4_interface 192.168.100.100
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ Interface eth2
+
+ # The multicast sender uses a buffer to enqueue the packets
+ # that are going to be transmitted. The default size of this
+ # socket buffer is available at /proc/sys/net/core/wmem_default.
+ # This value determines the chances to have an overrun in the
+ # sender queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size
+ # of the sender buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ SndSocketBuffer 1249280
+
+ # The multicast receiver uses a buffer to enqueue the packets
+ # that the socket is pending to handle. The default size of this
+ # socket buffer is available at /proc/sys/net/core/rmem_default.
+ # This value determines the chances to have an overrun in the
+ # receiver queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size of
+ # the receiver buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming. This is a good
+ # property to achieve fault-tolerance. In case of doubt, do
+ # not modify this value.
+ #
+ Checksum on
+ }
+ #
+ # You can specify more than one dedicated link. Thus, if one dedicated
+ # link fails, conntrackd can fail-over to another. Note that adding
+ # more than one dedicated link does not mean that state-updates will
+ # be sent to all of them. There is only one active dedicated link at
+ # a given moment. The `Default' keyword indicates that this interface
+ # will be selected as the initial dedicated link. You can have
+ # up to 4 redundant dedicated links. Note: Use different multicast
+ # groups for every redundant link.
+ #
+ # Multicast Default {
+ # IPv4_address 225.0.0.51
+ # Group 3781
+ # IPv4_interface 192.168.100.101
+ # Interface eth3
+ # # SndSocketBuffer 1249280
+ # # RcvSocketBuffer 1249280
+ # Checksum on
+ # }
+
+ #
+ # You can use Unicast UDP instead of Multicast to propagate events.
+ # Note that you cannot use unicast UDP and Multicast at the same
+ # time, you can only select one.
+ #
+ # UDP {
+ #
+ # UDP address that this firewall uses to listen to events.
+ #
+ # IPv4_address 192.168.2.100
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_address fe80::215:58ff:fe28:5a27
+
+ #
+ # Destination UDP address that receives events, ie. the other
+ # firewall's dedicated link address.
+ #
+ # IPv4_Destination_Address 192.168.2.101
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_Destination_Address fe80::2d0:59ff:fe2a:775c
+
+ #
+ # UDP port used
+ #
+ # Port 3780
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ # Interface eth2
+
+ #
+ # The sender socket buffer size
+ #
+ # SndSocketBuffer 1249280
+
+ #
+ # The receiver socket buffer size
+ #
+ # RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming.
+ #
+ # Checksum on
+ # }
+}
+
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon, this value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # very low value reduces the chances to lose state-change events.
+ # Default is 0 but this example file sets it to most favourable
+ # scheduling as this is generally a good idea. See man nice(1) for
+ # more information.
+ #
+ Nice -20
+
+ #
+ # Number of buckets in the cache hashtable. The bigger it is,
+ # the closer it gets to O(1) at the cost of consuming more memory.
+ # Read some documents about tuning hashtables for further reference.
+ #
+ HashSize 32768
+
+ #
+ # Maximum number of conntracks, it should be double of:
+ # $ cat /proc/sys/net/netfilter/nf_conntrack_max
+ # since the daemon may keep some dead entries cached for possible
+ # retransmission during state synchronization.
+ #
+ HashLimit 131072
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink event socket buffer size. If you do not specify this clause,
+ # the default buffer size value in /proc/net/core/rmem_default is
+ # used. This default value is usually around 100 Kbytes which is
+ # fairly small for busy firewalls. This leads to event message dropping
+ # and high CPU consumption. This example configuration file sets the
+ # size to 2 MBytes to avoid this sort of problems.
+ #
+ NetlinkBufferSize 2097152
+
+ #
+ # The daemon doubles the size of the netlink event socket buffer size
+ # if it detects netlink event message dropping. This clause sets the
+ # maximum buffer size growth that can be reached. This example file
+ # sets the size to 8 MBytes.
+ #
+ NetlinkBufferSizeMaxGrowth 8388608
+
+ #
+ # If the daemon detects that Netlink is dropping state-change events,
+ # it automatically schedules a resynchronization against the Kernel
+ # after 30 seconds (default value). Resynchronizations are expensive
+ # in terms of CPU consumption since the daemon has to get the full
+ # kernel state-table and purge state-entries that do not exist anymore.
+ # Be careful of setting a very small value here. You have the following
+ # choices: On (enabled, use default 30 seconds value), Off (disabled)
+ # or Value (in seconds, to set a specific amount of time). If not
+ # specified, the daemon assumes that this option is enabled.
+ #
+ # NetlinkOverrunResync On
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # The daemon prioritizes the handling of state-change events coming
+ # from the core. With this clause, you can set the maximum number of
+ # state-change events (those coming from kernel-space) that the daemon
+ # will handle after which it will handle other events coming from the
+ # network or userspace. A low value improves interactivity (in terms of
+ # real-time behaviour) at the cost of extra CPU consumption.
+ # Default (if not set) is 100.
+ #
+ # EventIterationLimit 100
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ # You can select if conntrackd filters the event messages from
+ # user-space or kernel-space. The kernel-space event filtering
+ # saves some CPU cycles by avoiding the copy of the event message
+ # from kernel-space to user-space. The kernel-space event filtering
+ # is prefered, however, you require a Linux kernel >= 2.6.29 to
+ # filter from kernel-space. If you want to select kernel-space
+ # event filtering, use the keyword 'Kernelspace' instead of
+ # 'Userspace'.
+ #
+ Filter From Userspace {
+ #
+ # Accept only certain protocols: You may want to replicate
+ # the state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's: Usually all the
+ # IP assigned to the firewall since local traffic must be
+ # ignored, only forwarded connections are worth to replicate.
+ # Note that these values depends on the local IPs that are
+ # assigned to the firewall.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ IPv4_address 192.168.0.100 # virtual IP 1
+ IPv4_address 192.168.1.100 # virtual IP 2
+ IPv4_address 192.168.0.1
+ IPv4_address 192.168.1.1
+ IPv4_address 192.168.100.100 # dedicated link ip
+ #
+ # You can also specify networks in format IP/cidr.
+ # IPv4_address 192.168.0.0/24
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # This option introduces a trade-off in the replication: it
+ # reduces CPU consumption at the cost of having lazy backup
+ # firewall replicas. The existing TCP states are: SYN_SENT,
+ # SYN_RECV, ESTABLISHED, FIN_WAIT, CLOSE_WAIT, LAST_ACK,
+ # TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
diff --git a/doc/sync/alarm/conntrackd.conf.rej b/doc/sync/alarm/conntrackd.conf.rej
new file mode 100644
index 0000000..108546f
--- /dev/null
+++ b/doc/sync/alarm/conntrackd.conf.rej
@@ -0,0 +1,30 @@
+*************** Sync {
+*** 23,36 ****
+
+ #
+ # If the firewall replica goes from primary to backup,
+- # the conntrackd -t command is invoked in the script.
+- # This command resets the timers of the conntracks that
+- # live in the kernel to this new value. This is useful
+- # to purge the connection tracking table of zombie entries
+- # and avoid clashes with old entries if you trigger
+- # several consecutive hand-overs.
+ #
+- PurgeTimeout 15
+
+ # Set the acknowledgement window size. If you decrease this
+ # value, the number of acknowlegdments increases. More
+--- 23,35 ----
+
+ #
+ # If the firewall replica goes from primary to backup,
++ # the conntrackd -t command is invoked in the script.
++ # This command schedules a flush of the table in N seconds.
++ # This is useful to purge the connection tracking table of
++ # zombie entries and avoid clashes with old entries if you
++ # trigger several consecutive hand-overs. Default is 60 seconds.
+ #
++ # PurgeTimeout 60
+
+ # Set the acknowledgement window size. If you decrease this
+ # value, the number of acknowlegdments increases. More
diff --git a/doc/sync/ftfw/README b/doc/sync/ftfw/README
new file mode 100644
index 0000000..a09db10
--- /dev/null
+++ b/doc/sync/ftfw/README
@@ -0,0 +1 @@
+This directory contains the files for the FT-FW based protocol
diff --git a/doc/sync/ftfw/conntrackd.conf b/doc/sync/ftfw/conntrackd.conf
new file mode 100644
index 0000000..df10aca
--- /dev/null
+++ b/doc/sync/ftfw/conntrackd.conf
@@ -0,0 +1,397 @@
+#
+# Synchronizer settings
+#
+Sync {
+ Mode FTFW {
+ #
+ # Size of the resend queue (in objects). This is the maximum
+ # number of objects that can be stored waiting to be confirmed
+ # via acknoledgment. If you keep this value low, the daemon
+ # will have less chances to recover state-changes under message
+ # omission. On the other hand, if you keep this value high,
+ # the daemon will consume more memory to store dead objects.
+ # Default is 131072 objects.
+ #
+ # ResendQueueSize 131072
+
+ #
+ # This parameter allows you to set an initial fixed timeout
+ # for the committed entries when this node goes from backup
+ # to primary. This mechanism provides a way to purge entries
+ # that were not recovered appropriately after the specified
+ # fixed timeout. If you set a low value, TCP entries in
+ # Established states with no traffic may hang. For example,
+ # an SSH connection without KeepAlive enabled. If not set,
+ # the daemon uses an approximate timeout value calculation
+ # mechanism. By default, this option is not set.
+ #
+ # CommitTimeout 180
+
+ #
+ # If the firewall replica goes from primary to backup,
+ # the conntrackd -t command is invoked in the script.
+ # This command schedules a flush of the table in N seconds.
+ # This is useful to purge the connection tracking table of
+ # zombie entries and avoid clashes with old entries if you
+ # trigger several consecutive hand-overs. Default is 60 seconds.
+ #
+ # PurgeTimeout 60
+
+ # Set the acknowledgement window size. If you decrease this
+ # value, the number of acknowlegdments increases. More
+ # acknowledgments means more overhead as conntrackd has to
+ # handle more control messages. On the other hand, if you
+ # increase this value, the resend queue gets more populated.
+ # This results in more overhead in the queue releasing.
+ # The following value is based on some practical experiments
+ # measuring the cycles spent by the acknowledgment handling
+ # with oprofile. If not set, default window size is 300.
+ #
+ # ACKWindowSize 300
+
+ #
+ # This clause allows you to disable the external cache. Thus,
+ # the state entries are directly injected into the kernel
+ # conntrack table. As a result, you save memory in user-space
+ # but you consume slots in the kernel conntrack table for
+ # backup state entries. Moreover, disabling the external cache
+ # means more CPU consumption. You need a Linux kernel
+ # >= 2.6.29 to use this feature. By default, this clause is
+ # set off. If you are installing conntrackd for first time,
+ # please read the user manual and I encourage you to consider
+ # using the fail-over scripts instead of enabling this option!
+ #
+ # DisableExternalCache Off
+ }
+
+ #
+ # Multicast IP and interface where messages are
+ # broadcasted (dedicated link). IMPORTANT: Make sure
+ # that iptables accepts traffic for destination
+ # 225.0.0.50, eg:
+ #
+ # iptables -I INPUT -d 225.0.0.50 -j ACCEPT
+ # iptables -I OUTPUT -d 225.0.0.50 -j ACCEPT
+ #
+ Multicast {
+ #
+ # Multicast address: The address that you use as destination
+ # in the synchronization messages. You do not have to add
+ # this IP to any of your existing interfaces. If any doubt,
+ # do not modify this value.
+ #
+ IPv4_address 225.0.0.50
+
+ #
+ # The multicast group that identifies the cluster. If any
+ # doubt, do not modify this value.
+ #
+ Group 3780
+
+ #
+ # IP address of the interface that you are going to use to
+ # send the synchronization messages. Remember that you must
+ # use a dedicated link for the synchronization messages.
+ #
+ IPv4_interface 192.168.100.100
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ Interface eth2
+
+ # The multicast sender uses a buffer to enqueue the packets
+ # that are going to be transmitted. The default size of this
+ # socket buffer is available at /proc/sys/net/core/wmem_default.
+ # This value determines the chances to have an overrun in the
+ # sender queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size
+ # of the sender buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ SndSocketBuffer 1249280
+
+ # The multicast receiver uses a buffer to enqueue the packets
+ # that the socket is pending to handle. The default size of this
+ # socket buffer is available at /proc/sys/net/core/rmem_default.
+ # This value determines the chances to have an overrun in the
+ # receiver queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size of
+ # the receiver buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming. This is a good
+ # property to achieve fault-tolerance. In case of doubt, do
+ # not modify this value.
+ #
+ Checksum on
+ }
+ #
+ # You can specify more than one dedicated link. Thus, if one dedicated
+ # link fails, conntrackd can fail-over to another. Note that adding
+ # more than one dedicated link does not mean that state-updates will
+ # be sent to all of them. There is only one active dedicated link at
+ # a given moment. The `Default' keyword indicates that this interface
+ # will be selected as the initial dedicated link. You can have
+ # up to 4 redundant dedicated links. Note: Use different multicast
+ # groups for every redundant link.
+ #
+ # Multicast Default {
+ # IPv4_address 225.0.0.51
+ # Group 3781
+ # IPv4_interface 192.168.100.101
+ # Interface eth3
+ # # SndSocketBuffer 1249280
+ # # RcvSocketBuffer 1249280
+ # Checksum on
+ # }
+
+ #
+ # You can use Unicast UDP instead of Multicast to propagate events.
+ # Note that you cannot use unicast UDP and Multicast at the same
+ # time, you can only select one.
+ #
+ # UDP {
+ #
+ # UDP address that this firewall uses to listen to events.
+ #
+ # IPv4_address 192.168.2.100
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_address fe80::215:58ff:fe28:5a27
+
+ #
+ # Destination UDP address that receives events, ie. the other
+ # firewall's dedicated link address.
+ #
+ # IPv4_Destination_Address 192.168.2.101
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_Destination_Address fe80::2d0:59ff:fe2a:775c
+
+ #
+ # UDP port used
+ #
+ # Port 3780
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ # Interface eth2
+
+ #
+ # The sender socket buffer size
+ #
+ # SndSocketBuffer 1249280
+
+ #
+ # The receiver socket buffer size
+ #
+ # RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming.
+ #
+ # Checksum on
+ # }
+
+}
+
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon, this value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # very low value reduces the chances to lose state-change events.
+ # Default is 0 but this example file sets it to most favourable
+ # scheduling as this is generally a good idea. See man nice(1) for
+ # more information.
+ #
+ Nice -20
+
+ #
+ # Select a different scheduler for the daemon, you can select between
+ # RR and FIFO and the process priority (minimum is 0, maximum is 99).
+ # See man sched_setscheduler(2) for more information. Using a RT
+ # scheduler reduces the chances to overrun the Netlink buffer.
+ #
+ # Scheduler {
+ # Type FIFO
+ # Priority 99
+ # }
+
+ #
+ # Number of buckets in the cache hashtable. The bigger it is,
+ # the closer it gets to O(1) at the cost of consuming more memory.
+ # Read some documents about tuning hashtables for further reference.
+ #
+ HashSize 32768
+
+ #
+ # Maximum number of conntracks, it should be double of:
+ # $ cat /proc/sys/net/netfilter/nf_conntrack_max
+ # since the daemon may keep some dead entries cached for possible
+ # retransmission during state synchronization.
+ #
+ HashLimit 131072
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink event socket buffer size. If you do not specify this clause,
+ # the default buffer size value in /proc/net/core/rmem_default is
+ # used. This default value is usually around 100 Kbytes which is
+ # fairly small for busy firewalls. This leads to event message dropping
+ # and high CPU consumption. This example configuration file sets the
+ # size to 2 MBytes to avoid this sort of problems.
+ #
+ NetlinkBufferSize 2097152
+
+ #
+ # The daemon doubles the size of the netlink event socket buffer size
+ # if it detects netlink event message dropping. This clause sets the
+ # maximum buffer size growth that can be reached. This example file
+ # sets the size to 8 MBytes.
+ #
+ NetlinkBufferSizeMaxGrowth 8388608
+
+ #
+ # If the daemon detects that Netlink is dropping state-change events,
+ # it automatically schedules a resynchronization against the Kernel
+ # after 30 seconds (default value). Resynchronizations are expensive
+ # in terms of CPU consumption since the daemon has to get the full
+ # kernel state-table and purge state-entries that do not exist anymore.
+ # Be careful of setting a very small value here. You have the following
+ # choices: On (enabled, use default 30 seconds value), Off (disabled)
+ # or Value (in seconds, to set a specific amount of time). If not
+ # specified, the daemon assumes that this option is enabled.
+ #
+ # NetlinkOverrunResync On
+
+ #
+ # If you want reliable event reporting over Netlink, set on this
+ # option. If you set on this clause, it is a good idea to set off
+ # NetlinkOverrunResync. This option is off by default and you need
+ # a Linux kernel >= 2.6.31.
+ #
+ # NetlinkEventsReliable Off
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # The daemon prioritizes the handling of state-change events coming
+ # from the core. With this clause, you can set the maximum number of
+ # state-change events (those coming from kernel-space) that the daemon
+ # will handle after which it will handle other events coming from the
+ # network or userspace. A low value improves interactivity (in terms of
+ # real-time behaviour) at the cost of extra CPU consumption.
+ # Default (if not set) is 100.
+ #
+ # EventIterationLimit 100
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ # You can select if conntrackd filters the event messages from
+ # user-space or kernel-space. The kernel-space event filtering
+ # saves some CPU cycles by avoiding the copy of the event message
+ # from kernel-space to user-space. The kernel-space event filtering
+ # is prefered, however, you require a Linux kernel >= 2.6.29 to
+ # filter from kernel-space. If you want to select kernel-space
+ # event filtering, use the keyword 'Kernelspace' instead of
+ # 'Userspace'.
+ #
+ Filter From Userspace {
+ #
+ # Accept only certain protocols: You may want to replicate
+ # the state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ SCTP
+ DCCP
+ # ICMP # This requires a Linux kernel >= 2.6.31
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's: Usually all the
+ # IP assigned to the firewall since local traffic must be
+ # ignored, only forwarded connections are worth to replicate.
+ # Note that these values depends on the local IPs that are
+ # assigned to the firewall.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ IPv4_address 192.168.0.100 # virtual IP 1
+ IPv4_address 192.168.1.100 # virtual IP 2
+ IPv4_address 192.168.0.1
+ IPv4_address 192.168.1.1
+ IPv4_address 192.168.100.100 # dedicated link ip
+ #
+ # You can also specify networks in format IP/cidr.
+ # IPv4_address 192.168.0.0/24
+ #
+ # You can also specify an IPv6 address
+ # IPv6_address ::1
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # This option introduces a trade-off in the replication: it
+ # reduces CPU consumption at the cost of having lazy backup
+ # firewall replicas. The existing TCP states are: SYN_SENT,
+ # SYN_RECV, ESTABLISHED, FIN_WAIT, CLOSE_WAIT, LAST_ACK,
+ # TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
diff --git a/doc/sync/ftfw/conntrackd.conf.orig b/doc/sync/ftfw/conntrackd.conf.orig
new file mode 100644
index 0000000..c1208f9
--- /dev/null
+++ b/doc/sync/ftfw/conntrackd.conf.orig
@@ -0,0 +1,370 @@
+#
+# Synchronizer settings
+#
+Sync {
+ Mode FTFW {
+ #
+ # Size of the resend queue (in objects). This is the maximum
+ # number of objects that can be stored waiting to be confirmed
+ # via acknoledgment. If you keep this value low, the daemon
+ # will have less chances to recover state-changes under message
+ # omission. On the other hand, if you keep this value high,
+ # the daemon will consume more memory to store dead objects.
+ # Default is 131072 objects.
+ #
+ # ResendQueueSize 131072
+
+ #
+ # This parameter allows you to set an initial fixed timeout
+ # for the committed entries when this node goes from backup
+ # to primary. This mechanism provides a way to purge entries
+ # that were not recovered appropriately after the specified
+ # fixed timeout. If you set a low value, TCP entries in
+ # Established states with no traffic may hang. For example,
+ # an SSH connection without KeepAlive enabled. If not set,
+ # the daemon uses an approximate timeout value calculation
+ # mechanism. By default, this option is not set.
+ #
+ # CommitTimeout 180
+
+ #
+ # If the firewall replica goes from primary to backup,
+ # the conntrackd -t command is invoked in the script.
+ # This command schedules a flush of the table in N seconds.
+ # This is useful to purge the connection tracking table of
+ # zombie entries and avoid clashes with old entries if you
+ # trigger several consecutive hand-overs. Default is 60 seconds.
+ #
+ # PurgeTimeout 60
+
+ # Set the acknowledgement window size. If you decrease this
+ # value, the number of acknowlegdments increases. More
+ # acknowledgments means more overhead as conntrackd has to
+ # handle more control messages. On the other hand, if you
+ # increase this value, the resend queue gets more populated.
+ # This results in more overhead in the queue releasing.
+ # The following value is based on some practical experiments
+ # measuring the cycles spent by the acknowledgment handling
+ # with oprofile. If not set, default window size is 300.
+ #
+ # ACKWindowSize 300
+ }
+
+ #
+ # Multicast IP and interface where messages are
+ # broadcasted (dedicated link). IMPORTANT: Make sure
+ # that iptables accepts traffic for destination
+ # 225.0.0.50, eg:
+ #
+ # iptables -I INPUT -d 225.0.0.50 -j ACCEPT
+ # iptables -I OUTPUT -d 225.0.0.50 -j ACCEPT
+ #
+ Multicast {
+ #
+ # Multicast address: The address that you use as destination
+ # in the synchronization messages. You do not have to add
+ # this IP to any of your existing interfaces. If any doubt,
+ # do not modify this value.
+ #
+ IPv4_address 225.0.0.50
+
+ #
+ # The multicast group that identifies the cluster. If any
+ # doubt, do not modify this value.
+ #
+ Group 3780
+
+ #
+ # IP address of the interface that you are going to use to
+ # send the synchronization messages. Remember that you must
+ # use a dedicated link for the synchronization messages.
+ #
+ IPv4_interface 192.168.100.100
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ Interface eth2
+
+ # The multicast sender uses a buffer to enqueue the packets
+ # that are going to be transmitted. The default size of this
+ # socket buffer is available at /proc/sys/net/core/wmem_default.
+ # This value determines the chances to have an overrun in the
+ # sender queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size
+ # of the sender buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ SndSocketBuffer 1249280
+
+ # The multicast receiver uses a buffer to enqueue the packets
+ # that the socket is pending to handle. The default size of this
+ # socket buffer is available at /proc/sys/net/core/rmem_default.
+ # This value determines the chances to have an overrun in the
+ # receiver queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size of
+ # the receiver buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ #
+ RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming. This is a good
+ # property to achieve fault-tolerance. In case of doubt, do
+ # not modify this value.
+ #
+ Checksum on
+ }
+ #
+ # You can specify more than one dedicated link. Thus, if one dedicated
+ # link fails, conntrackd can fail-over to another. Note that adding
+ # more than one dedicated link does not mean that state-updates will
+ # be sent to all of them. There is only one active dedicated link at
+ # a given moment. The `Default' keyword indicates that this interface
+ # will be selected as the initial dedicated link. You can have
+ # up to 4 redundant dedicated links. Note: Use different multicast
+ # groups for every redundant link.
+ #
+ # Multicast Default {
+ # IPv4_address 225.0.0.51
+ # Group 3781
+ # IPv4_interface 192.168.100.101
+ # Interface eth3
+ # # SndSocketBuffer 1249280
+ # # RcvSocketBuffer 1249280
+ # Checksum on
+ # }
+
+ #
+ # You can use Unicast UDP instead of Multicast to propagate events.
+ # Note that you cannot use unicast UDP and Multicast at the same
+ # time, you can only select one.
+ #
+ # UDP {
+ #
+ # UDP address that this firewall uses to listen to events.
+ #
+ # IPv4_address 192.168.2.100
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_address fe80::215:58ff:fe28:5a27
+
+ #
+ # Destination UDP address that receives events, ie. the other
+ # firewall's dedicated link address.
+ #
+ # IPv4_Destination_Address 192.168.2.101
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_Destination_Address fe80::2d0:59ff:fe2a:775c
+
+ #
+ # UDP port used
+ #
+ # Port 3780
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ # Interface eth2
+
+ #
+ # The sender socket buffer size
+ #
+ # SndSocketBuffer 1249280
+
+ #
+ # The receiver socket buffer size
+ #
+ # RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming.
+ #
+ # Checksum on
+ # }
+}
+
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon, this value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # very low value reduces the chances to lose state-change events.
+ # Default is 0 but this example file sets it to most favourable
+ # scheduling as this is generally a good idea. See man nice(1) for
+ # more information.
+ #
+ Nice -20
+
+ #
+ # Select a different scheduler for the daemon, you can select between
+ # RR and FIFO and the process priority (minimum is 0, maximum is 99).
+ # See man sched_setscheduler(2) for more information. Using a RT
+ # scheduler reduces the chances to overrun the Netlink buffer.
+ #
+ # Scheduler {
+ # Type FIFO
+ # Priority 99
+ # }
+
+ #
+ # Number of buckets in the cache hashtable. The bigger it is,
+ # the closer it gets to O(1) at the cost of consuming more memory.
+ # Read some documents about tuning hashtables for further reference.
+ #
+ HashSize 32768
+
+ #
+ # Maximum number of conntracks, it should be double of:
+ # $ cat /proc/sys/net/netfilter/nf_conntrack_max
+ # since the daemon may keep some dead entries cached for possible
+ # retransmission during state synchronization.
+ #
+ HashLimit 131072
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink event socket buffer size. If you do not specify this clause,
+ # the default buffer size value in /proc/net/core/rmem_default is
+ # used. This default value is usually around 100 Kbytes which is
+ # fairly small for busy firewalls. This leads to event message dropping
+ # and high CPU consumption. This example configuration file sets the
+ # size to 2 MBytes to avoid this sort of problems.
+ #
+ NetlinkBufferSize 2097152
+
+ #
+ # The daemon doubles the size of the netlink event socket buffer size
+ # if it detects netlink event message dropping. This clause sets the
+ # maximum buffer size growth that can be reached. This example file
+ # sets the size to 8 MBytes.
+ #
+ NetlinkBufferSizeMaxGrowth 8388608
+
+ #
+ # If the daemon detects that Netlink is dropping state-change events,
+ # it automatically schedules a resynchronization against the Kernel
+ # after 30 seconds (default value). Resynchronizations are expensive
+ # in terms of CPU consumption since the daemon has to get the full
+ # kernel state-table and purge state-entries that do not exist anymore.
+ # Be careful of setting a very small value here. You have the following
+ # choices: On (enabled, use default 30 seconds value), Off (disabled)
+ # or Value (in seconds, to set a specific amount of time). If not
+ # specified, the daemon assumes that this option is enabled.
+ #
+ # NetlinkOverrunResync On
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # The daemon prioritizes the handling of state-change events coming
+ # from the core. With this clause, you can set the maximum number of
+ # state-change events (those coming from kernel-space) that the daemon
+ # will handle after which it will handle other events coming from the
+ # network or userspace. A low value improves interactivity (in terms of
+ # real-time behaviour) at the cost of extra CPU consumption.
+ # Default (if not set) is 100.
+ #
+ # EventIterationLimit 100
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ # You can select if conntrackd filters the event messages from
+ # user-space or kernel-space. The kernel-space event filtering
+ # saves some CPU cycles by avoiding the copy of the event message
+ # from kernel-space to user-space. The kernel-space event filtering
+ # is prefered, however, you require a Linux kernel >= 2.6.29 to
+ # filter from kernel-space. If you want to select kernel-space
+ # event filtering, use the keyword 'Kernelspace' instead of
+ # 'Userspace'.
+ #
+ Filter From Userspace {
+ #
+ # Accept only certain protocols: You may want to replicate
+ # the state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ SCTP
+ DCCP
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's: Usually all the
+ # IP assigned to the firewall since local traffic must be
+ # ignored, only forwarded connections are worth to replicate.
+ # Note that these values depends on the local IPs that are
+ # assigned to the firewall.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ IPv4_address 192.168.0.100 # virtual IP 1
+ IPv4_address 192.168.1.100 # virtual IP 2
+ IPv4_address 192.168.0.1
+ IPv4_address 192.168.1.1
+ IPv4_address 192.168.100.100 # dedicated link ip
+ #
+ # You can also specify networks in format IP/cidr.
+ # IPv4_address 192.168.0.0/24
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # This option introduces a trade-off in the replication: it
+ # reduces CPU consumption at the cost of having lazy backup
+ # firewall replicas. The existing TCP states are: SYN_SENT,
+ # SYN_RECV, ESTABLISHED, FIN_WAIT, CLOSE_WAIT, LAST_ACK,
+ # TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
diff --git a/doc/sync/keepalived-multi1.conf b/doc/sync/keepalived-multi1.conf
new file mode 100644
index 0000000..5ffb318
--- /dev/null
+++ b/doc/sync/keepalived-multi1.conf
@@ -0,0 +1,71 @@
+#
+# Simple script for multi-primary setups
+#
+
+vrrp_sync_group G1 { # must be before vrrp_instance declaration
+ group {
+ VI_1
+ VI_2
+ }
+ notify_master "/etc/conntrackd/multiprimary.sh primary 1"
+ notify_backup "/etc/conntrackd/multiprimary.sh backup 1"
+ notify_fault "/etc/conntrackd/multiprimary.sh fault 1"
+}
+
+vrrp_sync_group G2 { # must be before vrrp_instance declaration
+ group {
+ VI_3
+ VI_4
+ }
+ notify_master "/etc/conntrackd/multiprimary.sh primary 2"
+ notify_backup "/etc/conntrackd/multiprimary.sh backup 2"
+ notify_fault "/etc/conntrackd/multiprimary.sh fault 2"
+}
+
+vrrp_instance VI_1 {
+ interface eth1
+ state SLAVE
+ virtual_router_id 61
+ priority 90
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
+
+vrrp_instance VI_2 {
+ interface eth2
+ state SLAVE
+ virtual_router_id 61
+ priority 90
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
+
+vrrp_instance VI_3 {
+ interface eth1
+ state SLAVE
+ virtual_router_id 62
+ priority 10
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
+
+vrrp_instance VI_4 {
+ interface eth2
+ state SLAVE
+ virtual_router_id 62
+ priority 10
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
diff --git a/doc/sync/keepalived-multi2.conf b/doc/sync/keepalived-multi2.conf
new file mode 100644
index 0000000..91ab019
--- /dev/null
+++ b/doc/sync/keepalived-multi2.conf
@@ -0,0 +1,71 @@
+#
+# Simple script for multi-primary setups
+#
+
+vrrp_sync_group G1 { # must be before vrrp_instance declaration
+ group {
+ VI_1
+ VI_2
+ }
+ notify_master "/etc/conntrackd/multiprimary.sh primary 1"
+ notify_backup "/etc/conntrackd/multiprimary.sh backup 1"
+ notify_fault "/etc/conntrackd/multiprimary.sh fault 1"
+}
+
+vrrp_sync_group G2 { # must be before vrrp_instance declaration
+ group {
+ VI_3
+ VI_4
+ }
+ notify_master "/etc/conntrackd/multiprimary.sh primary 2"
+ notify_backup "/etc/conntrackd/multiprimary.sh backup 2"
+ notify_fault "/etc/conntrackd/multiprimary.sh fault 2"
+}
+
+vrrp_instance VI_1 {
+ interface eth1
+ state SLAVE
+ virtual_router_id 61
+ priority 10
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
+
+vrrp_instance VI_2 {
+ interface eth2
+ state SLAVE
+ virtual_router_id 61
+ priority 10
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
+
+vrrp_instance VI_3 {
+ interface eth1
+ state SLAVE
+ virtual_router_id 62
+ priority 90
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
+
+vrrp_instance VI_4 {
+ interface eth2
+ state SLAVE
+ virtual_router_id 62
+ priority 90
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+}
diff --git a/doc/sync/keepalived.conf b/doc/sync/keepalived.conf
new file mode 100644
index 0000000..84f1383
--- /dev/null
+++ b/doc/sync/keepalived.conf
@@ -0,0 +1,43 @@
+#
+# Simple script for primary-backup setups
+#
+
+vrrp_sync_group G1 { # must be before vrrp_instance declaration
+ group {
+ VI_1
+ VI_2
+ }
+ notify_master "/etc/conntrackd/primary-backup.sh primary"
+ notify_backup "/etc/conntrackd/primary-backup.sh backup"
+ notify_fault "/etc/conntrackd/primary-backup.sh fault"
+}
+
+vrrp_instance VI_1 {
+ interface eth1
+ state SLAVE
+ virtual_router_id 61
+ priority 80
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+ virtual_ipaddress {
+ 192.168.0.100 # default CIDR mask is /32
+ }
+}
+
+vrrp_instance VI_2 {
+ interface eth0
+ state SLAVE
+ virtual_router_id 62
+ priority 80
+ advert_int 3
+ authentication {
+ auth_type PASS
+ auth_pass papas_con_tomate
+ }
+ virtual_ipaddress {
+ 192.168.1.100
+ }
+}
diff --git a/doc/sync/multiprimary.sh b/doc/sync/multiprimary.sh
new file mode 100755
index 0000000..5c585c9
--- /dev/null
+++ b/doc/sync/multiprimary.sh
@@ -0,0 +1,212 @@
+#!/bin/sh
+#
+# (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>
+#
+# This software may be used and distributed according to the terms
+# of the GNU General Public License, incorporated herein by reference.
+#
+
+#
+# This is the node ID, must be >= 1 and <= 2. You have to CHANGE IT according
+# to the number of node where you are.
+#
+NODEID=1
+
+CONNTRACKD_BIN="/usr/sbin/conntrackd"
+CONNTRACKD_LOCK="/var/lock/conntrack.lock"
+CONNTRACKD_CONFIG="/etc/conntrackd/conntrackd.conf"
+
+ETHER1="eth1"
+ETHER2="eth2"
+
+state_primary()
+{
+ #
+ # commit the external cache into the kernel table
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -c
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -c"
+ fi
+
+ #
+ # flush the internal and the external caches
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -f
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -f"
+ fi
+
+ #
+ # resynchronize my internal cache to the kernel table
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -R
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -R"
+ fi
+
+ #
+ # send a bulk update to backups
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -B
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -B"
+ fi
+}
+
+state_backup() {
+ #
+ # is conntrackd running? request some statistics to check it
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -s
+ if [ $? -eq 1 ]
+ then
+ #
+ # something's wrong, do we have a lock file?
+ #
+ if [ -f $CONNTRACKD_LOCK ]
+ then
+ logger "WARNING: conntrackd was not cleanly stopped."
+ logger "If you suspect that it has crashed:"
+ logger "1) Enable coredumps"
+ logger "2) Try to reproduce the problem"
+ logger "3) Post the coredump to netfilter-devel@vger.kernel.org"
+ rm -f $CONNTRACKD_LOCK
+ fi
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -d
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: cannot launch conntrackd"
+ exit 1
+ fi
+ fi
+ #
+ # shorten kernel conntrack timers to remove the zombie entries.
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -t
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -t"
+ fi
+
+ #
+ # request resynchronization with master firewall replica (if any)
+ # Note: this does nothing in the alarm approach.
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -n
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -n"
+ fi
+}
+
+state_fault() {
+ #
+ # shorten kernel conntrack timers to remove the zombie entries.
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -t
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -t"
+ fi
+}
+
+iptables_add_cluster_rule() {
+ iptables -I CLUSTERDEV1 -t mangle -m cluster \
+ --cluster-total-nodes 2 --cluster-local-node $1 \
+ --cluster-hash-seed 0xdeadbeed -j MARK --set-mark 0xffff
+ iptables -I CLUSTERDEV2 -t mangle -m cluster \
+ --cluster-total-nodes 2 --cluster-local-node $1 \
+ --cluster-hash-seed 0xdeadbeed -j MARK --set-mark 0xffff
+}
+
+iptables_del_cluster_rule() {
+ iptables -D CLUSTERDEV1 -t mangle -m cluster \
+ --cluster-total-nodes 2 --cluster-local-node $1 \
+ --cluster-hash-seed 0xdeadbeed -j MARK --set-mark 0xffff
+ iptables -D CLUSTERDEV2 -t mangle -m cluster \
+ --cluster-total-nodes 2 --cluster-local-node $1 \
+ --cluster-hash-seed 0xdeadbeed -j MARK --set-mark 0xffff
+}
+
+iptables_start_cluster_rule() {
+ iptables -N CLUSTERDEV1 -t mangle
+ iptables -N CLUSTERDEV2 -t mangle
+ iptables_add_cluster_rule $1
+ iptables -A CLUSTERDEV1 -t mangle -m mark ! --mark 0xffff -j DROP
+ iptables -A CLUSTERDEV2 -t mangle -m mark ! --mark 0xffff -j DROP
+ iptables -I PREROUTING -t mangle -p vrrp -j ACCEPT
+ iptables -A PREROUTING -t mangle -i $ETHER1 -j CLUSTERDEV1
+ iptables -A PREROUTING -t mangle -i $ETHER2 -j CLUSTERDEV2
+}
+
+iptables_stop_cluster_rule() {
+ iptables -D PREROUTING -t mangle -i $ETHER1 -j CLUSTERDEV1
+ iptables -D PREROUTING -t mangle -i $ETHER2 -j CLUSTERDEV2
+ iptables -D PREROUTING -t mangle -p vrrp -j ACCEPT
+ iptables -F CLUSTERDEV1 -t mangle
+ iptables -F CLUSTERDEV2 -t mangle
+ iptables -X CLUSTERDEV1 -t mangle
+ iptables -X CLUSTERDEV2 -t mangle
+}
+
+# this can be called without options
+case "$1" in
+ start)
+ iptables_start_cluster_rule $NODEID
+ exit 0
+ ;;
+ stop)
+ iptables_stop_cluster_rule $NODEID
+ exit 0
+ ;;
+esac
+
+if [ $# -ne 2 ]
+then
+ logger "ERROR: missing arguments"
+ echo "Usage: $0 {primary|backup|fault|start|stop} {nodeid}"
+ exit 1
+fi
+
+case "$1" in
+ primary)
+ #
+ # We are entering the MASTER state, it may be for G1 or G2, but we
+ # commit the external cache anyway.
+ #
+ state_primary
+ iptables_add_cluster_rule $2
+ ;;
+ backup)
+ #
+ # We are entering the BACKUP state. We can enter it from G1 or G2.
+ # Assuming that we are node 1 and that we have entered BACKUP in G2,
+ # this means that node 2 has come back to life. In that case, skip
+ # state_backup because we are still in MASTER state for G1.
+ #
+ if [ $NODEID -eq $2 ]
+ then
+ state_backup
+ fi
+ iptables_del_cluster_rule $2
+ ;;
+ fault)
+ #
+ # We are entering the FAULT state, something bad is happening to us.
+ #
+ state_fault
+ iptables_del_cluster_rule $2
+ ;;
+ *)
+ logger "ERROR: unknown state transition"
+ echo "Usage: $0 {primary|backup|fault|start|stop} {nodeid}"
+ exit 1
+ ;;
+esac
+
+exit 0
diff --git a/doc/sync/notrack/README b/doc/sync/notrack/README
new file mode 100644
index 0000000..b064e21
--- /dev/null
+++ b/doc/sync/notrack/README
@@ -0,0 +1,3 @@
+This directory contains the files for the NOTRACK replication protocol. This
+protocol provides best effort delivery. Therefore, it is unreliable unless
+that you select TCP-based state-synchronization.
diff --git a/doc/sync/notrack/conntrackd.conf b/doc/sync/notrack/conntrackd.conf
new file mode 100644
index 0000000..f8bccc4
--- /dev/null
+++ b/doc/sync/notrack/conntrackd.conf
@@ -0,0 +1,434 @@
+#
+# Synchronizer settings
+#
+Sync {
+ Mode NOTRACK {
+ #
+ # This parameter allows you to set an initial fixed timeout
+ # for the committed entries when this node goes from backup
+ # to primary. This mechanism provides a way to purge entries
+ # that were not recovered appropriately after the specified
+ # fixed timeout. If you set a low value, TCP entries in
+ # Established states with no traffic may hang. For example,
+ # an SSH connection without KeepAlive enabled. If not set,
+ # the daemon uses an approximate timeout value calculation
+ # mechanism. By default, this option is not set.
+ #
+ # CommitTimeout 180
+
+ #
+ # If the firewall replica goes from primary to backup,
+ # the conntrackd -t command is invoked in the script.
+ # This command schedules a flush of the table in N seconds.
+ # This is useful to purge the connection tracking table of
+ # zombie entries and avoid clashes with old entries if you
+ # trigger several consecutive hand-overs. Default is 60 seconds.
+ #
+ # PurgeTimeout 60
+
+ #
+ # This clause allows you to disable the internal cache. Thus,
+ # the synchronization messages are directly send through
+ # the dedicated link. This option is set of off by default.
+ #
+ # DisableInternalCache Off
+
+ #
+ # This clause allows you to disable the external cache. Thus,
+ # the state entries are directly injected into the kernel
+ # conntrack table. As a result, you save memory in user-space
+ # but you consume slots in the kernel conntrack table for
+ # backup state entries. Moreover, disabling the external cache
+ # means more CPU consumption. You need a Linux kernel
+ # >= 2.6.29 to use this feature. By default, this clause is
+ # set off. If you are installing conntrackd for first time,
+ # please read the user manual and I encourage you to consider
+ # using the fail-over scripts instead of enabling this option!
+ #
+ # DisableExternalCache Off
+ }
+
+ #
+ # Multicast IP and interface where messages are
+ # broadcasted (dedicated link). IMPORTANT: Make sure
+ # that iptables accepts traffic for destination
+ # 225.0.0.50, eg:
+ #
+ # iptables -I INPUT -d 225.0.0.50 -j ACCEPT
+ # iptables -I OUTPUT -d 225.0.0.50 -j ACCEPT
+ #
+ Multicast {
+ #
+ # Multicast address: The address that you use as destination
+ # in the synchronization messages. You do not have to add
+ # this IP to any of your existing interfaces. If any doubt,
+ # do not modify this value.
+ #
+ IPv4_address 225.0.0.50
+
+ #
+ # The multicast group that identifies the cluster. If any
+ # doubt, do not modify this value.
+ #
+ Group 3780
+
+ #
+ # IP address of the interface that you are going to use to
+ # send the synchronization messages. Remember that you must
+ # use a dedicated link for the synchronization messages.
+ #
+ IPv4_interface 192.168.100.100
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ Interface eth2
+
+ # The multicast sender uses a buffer to enqueue the packets
+ # that are going to be transmitted. The default size of this
+ # socket buffer is available at /proc/sys/net/core/wmem_default.
+ # This value determines the chances to have an overrun in the
+ # sender queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size
+ # of the sender buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ # Note: This protocol is best effort, it is really recommended
+ # to increase the buffer size.
+ #
+ SndSocketBuffer 1249280
+
+ # The multicast receiver uses a buffer to enqueue the packets
+ # that the socket is pending to handle. The default size of this
+ # socket buffer is available at /proc/sys/net/core/rmem_default.
+ # This value determines the chances to have an overrun in the
+ # receiver queue. The overrun results packet loss, thus, losing
+ # state information that would have to be retransmitted. If you
+ # notice some packet loss, you may want to increase the size of
+ # of the sender buffer. The default size is usually around
+ # ~100 KBytes which is fairly small for busy firewalls.
+ # Note: This protocol is best effort, it is really recommended
+ # to increase the buffer size.
+ #
+ RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming. This is a good
+ # property to achieve fault-tolerance. In case of doubt, do
+ # not modify this value.
+ #
+ Checksum on
+ }
+ #
+ # You can specify more than one dedicated link. Thus, if one dedicated
+ # link fails, conntrackd can fail-over to another. Note that adding
+ # more than one dedicated link does not mean that state-updates will
+ # be sent to all of them. There is only one active dedicated link at
+ # a given moment. The `Default' keyword indicates that this interface
+ # will be selected as the initial dedicated link. You can have
+ # up to 4 redundant dedicated links. Note: Use different multicast
+ # groups for every redundant link.
+ #
+ # Multicast Default {
+ # IPv4_address 225.0.0.51
+ # Group 3781
+ # IPv4_interface 192.168.100.101
+ # Interface eth3
+ # # SndSocketBuffer 1249280
+ # # RcvSocketBuffer 1249280
+ # Checksum on
+ # }
+
+ #
+ # You can use Unicast UDP instead of Multicast to propagate events.
+ # Note that you cannot use unicast UDP and Multicast at the same
+ # time, you can only select one.
+ #
+ # UDP {
+ #
+ # UDP address that this firewall uses to listen to events.
+ #
+ # IPv4_address 192.168.2.100
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_address fe80::215:58ff:fe28:5a27
+
+ #
+ # Destination UDP address that receives events, ie. the other
+ # firewall's dedicated link address.
+ #
+ # IPv4_Destination_Address 192.168.2.101
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_Destination_Address fe80::2d0:59ff:fe2a:775c
+
+ #
+ # UDP port used
+ #
+ # Port 3780
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ # Interface eth2
+
+ #
+ # The sender socket buffer size
+ #
+ # SndSocketBuffer 1249280
+
+ #
+ # The receiver socket buffer size
+ #
+ # RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming.
+ #
+ # Checksum on
+ # }
+
+ #
+ # You can also use Unicast TCP to propagate events. Thus, the NOTRACK
+ # mode becomes reliable.
+ #
+ # TCP {
+ #
+ # TCP address that this firewall uses to listen to events.
+ #
+ # IPv4_address 192.168.2.100
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_address fe80::215:58ff:fe28:5a27
+
+ #
+ # Destination TCP address that receives events, ie. the other
+ # firewall's dedicated link address.
+ #
+ # IPv4_Destination_Address 192.168.2.101
+ #
+ # or you may want to use an IPv6 address:
+ #
+ # IPv6_Destination_Address fe80::2d0:59ff:fe2a:775c
+
+ #
+ # TCP port used
+ #
+ # Port 3780
+
+ #
+ # The name of the interface that you are going to use to
+ # send the synchronization messages.
+ #
+ # Interface eth2
+
+ #
+ # The sender socket buffer size
+ #
+ # SndSocketBuffer 1249280
+
+ #
+ # The receiver socket buffer size
+ #
+ # RcvSocketBuffer 1249280
+
+ #
+ # Enable/Disable message checksumming.
+ #
+ # Checksum on
+ # }
+}
+
+#
+# General settings
+#
+General {
+ #
+ # Set the nice value of the daemon, this value goes from -20
+ # (most favorable scheduling) to 19 (least favorable). Using a
+ # very low value reduces the chances to lose state-change events.
+ # Default is 0 but this example file sets it to most favourable
+ # scheduling as this is generally a good idea. See man nice(1) for
+ # more information.
+ #
+ Nice -20
+
+ #
+ # Select a different scheduler for the daemon, you can select between
+ # RR and FIFO and the process priority (minimum is 0, maximum is 99).
+ # See man sched_setscheduler(2) for more information. Using a RT
+ # scheduler reduces the chances to overrun the Netlink buffer.
+ #
+ # Scheduler {
+ # Type FIFO
+ # Priority 99
+ # }
+
+ #
+ # Number of buckets in the cache hashtable. The bigger it is,
+ # the closer it gets to O(1) at the cost of consuming more memory.
+ # Read some documents about tuning hashtables for further reference.
+ #
+ HashSize 32768
+
+ #
+ # Maximum number of conntracks, it should be double of:
+ # $ cat /proc/sys/net/netfilter/nf_conntrack_max
+ # since the daemon may keep some dead entries cached for possible
+ # retransmission during state synchronization.
+ #
+ HashLimit 131072
+
+ #
+ # Logfile: on (/var/log/conntrackd.log), off, or a filename
+ # Default: off
+ #
+ LogFile on
+
+ #
+ # Syslog: on, off or a facility name (daemon (default) or local0..7)
+ # Default: off
+ #
+ #Syslog on
+
+ #
+ # Lockfile
+ #
+ LockFile /var/lock/conntrack.lock
+
+ #
+ # Unix socket configuration
+ #
+ UNIX {
+ Path /var/run/conntrackd.ctl
+ Backlog 20
+ }
+
+ #
+ # Netlink event socket buffer size. If you do not specify this clause,
+ # the default buffer size value in /proc/net/core/rmem_default is
+ # used. This default value is usually around 100 Kbytes which is
+ # fairly small for busy firewalls. This leads to event message dropping
+ # and high CPU consumption. This example configuration file sets the
+ # size to 2 MBytes to avoid this sort of problems.
+ #
+ NetlinkBufferSize 2097152
+
+ #
+ # The daemon doubles the size of the netlink event socket buffer size
+ # if it detects netlink event message dropping. This clause sets the
+ # maximum buffer size growth that can be reached. This example file
+ # sets the size to 8 MBytes.
+ #
+ NetlinkBufferSizeMaxGrowth 8388608
+
+ #
+ # If the daemon detects that Netlink is dropping state-change events,
+ # it automatically schedules a resynchronization against the Kernel
+ # after 30 seconds (default value). Resynchronizations are expensive
+ # in terms of CPU consumption since the daemon has to get the full
+ # kernel state-table and purge state-entries that do not exist anymore.
+ # Be careful of setting a very small value here. You have the following
+ # choices: On (enabled, use default 30 seconds value), Off (disabled)
+ # or Value (in seconds, to set a specific amount of time). If not
+ # specified, the daemon assumes that this option is enabled.
+ #
+ # NetlinkOverrunResync On
+
+ # If you want reliable event reporting over Netlink, set on this
+ # option. If you set on this clause, it is a good idea to set off
+ # NetlinkOverrunResync. This option is off by default and you need
+ # a Linux kernel >= 2.6.31.
+ #
+ # NetlinkEventsReliable Off
+
+ #
+ # By default, the daemon receives state updates following an
+ # event-driven model. You can modify this behaviour by switching to
+ # polling mode with the PollSecs clause. This clause tells conntrackd
+ # to dump the states in the kernel every N seconds. With regards to
+ # synchronization mode, the polling mode can only guarantee that
+ # long-lifetime states are recovered. The main advantage of this method
+ # is the reduction in the state replication at the cost of reducing the
+ # chances of recovering connections.
+ #
+ # PollSecs 15
+
+ #
+ # The daemon prioritizes the handling of state-change events coming
+ # from the core. With this clause, you can set the maximum number of
+ # state-change events (those coming from kernel-space) that the daemon
+ # will handle after which it will handle other events coming from the
+ # network or userspace. A low value improves interactivity (in terms of
+ # real-time behaviour) at the cost of extra CPU consumption.
+ # Default (if not set) is 100.
+ #
+ # EventIterationLimit 100
+
+ #
+ # Event filtering: This clause allows you to filter certain traffic,
+ # There are currently three filter-sets: Protocol, Address and
+ # State. The filter is attached to an action that can be: Accept or
+ # Ignore. Thus, you can define the event filtering policy of the
+ # filter-sets in positive or negative logic depending on your needs.
+ # You can select if conntrackd filters the event messages from
+ # user-space or kernel-space. The kernel-space event filtering
+ # saves some CPU cycles by avoiding the copy of the event message
+ # from kernel-space to user-space. The kernel-space event filtering
+ # is prefered, however, you require a Linux kernel >= 2.6.29 to
+ # filter from kernel-space. If you want to select kernel-space
+ # event filtering, use the keyword 'Kernelspace' instead of
+ # 'Userspace'.
+ #
+ Filter From Userspace {
+ #
+ # Accept only certain protocols: You may want to replicate
+ # the state of flows depending on their layer 4 protocol.
+ #
+ Protocol Accept {
+ TCP
+ SCTP
+ DCCP
+ # ICMP # This requires a Linux kernel >= 2.6.31
+ }
+
+ #
+ # Ignore traffic for a certain set of IP's: Usually all the
+ # IP assigned to the firewall since local traffic must be
+ # ignored, only forwarded connections are worth to replicate.
+ # Note that these values depends on the local IPs that are
+ # assigned to the firewall.
+ #
+ Address Ignore {
+ IPv4_address 127.0.0.1 # loopback
+ IPv4_address 192.168.0.100 # virtual IP 1
+ IPv4_address 192.168.1.100 # virtual IP 2
+ IPv4_address 192.168.0.1
+ IPv4_address 192.168.1.1
+ IPv4_address 192.168.100.100 # dedicated link ip
+ #
+ # You can also specify networks in format IP/cidr.
+ # IPv4_address 192.168.0.0/24
+ #
+ # You can also specify an IPv6 address
+ # IPv6_address ::1
+ }
+
+ #
+ # Uncomment this line below if you want to filter by flow state.
+ # This option introduces a trade-off in the replication: it
+ # reduces CPU consumption at the cost of having lazy backup
+ # firewall replicas. The existing TCP states are: SYN_SENT,
+ # SYN_RECV, ESTABLISHED, FIN_WAIT, CLOSE_WAIT, LAST_ACK,
+ # TIME_WAIT, CLOSED, LISTEN.
+ #
+ # State Accept {
+ # ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP
+ # }
+ }
+}
diff --git a/doc/sync/primary-backup.sh b/doc/sync/primary-backup.sh
new file mode 100755
index 0000000..34c1cfa
--- /dev/null
+++ b/doc/sync/primary-backup.sh
@@ -0,0 +1,124 @@
+#!/bin/sh
+#
+# (C) 2008 by Pablo Neira Ayuso <pablo@netfilter.org>
+#
+# This software may be used and distributed according to the terms
+# of the GNU General Public License, incorporated herein by reference.
+#
+# Description:
+#
+# This is the script for primary-backup setups for keepalived
+# (http://www.keepalived.org). You may adapt it to make it work with other
+# high-availability managers.
+#
+# Do not forget to include the required modifications to your keepalived.conf
+# file to invoke this script during keepalived's state transitions.
+#
+# Contributions to improve this script are welcome :).
+#
+
+CONNTRACKD_BIN=/usr/sbin/conntrackd
+CONNTRACKD_LOCK=/var/lock/conntrack.lock
+CONNTRACKD_CONFIG=/etc/conntrackd/conntrackd.conf
+
+case "$1" in
+ primary)
+ #
+ # commit the external cache into the kernel table
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -c
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -c"
+ fi
+
+ #
+ # flush the internal and the external caches
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -f
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -f"
+ fi
+
+ #
+ # resynchronize my internal cache to the kernel table
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -R
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -R"
+ fi
+
+ #
+ # send a bulk update to backups
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -B
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -B"
+ fi
+ ;;
+ backup)
+ #
+ # is conntrackd running? request some statistics to check it
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -s
+ if [ $? -eq 1 ]
+ then
+ #
+ # something's wrong, do we have a lock file?
+ #
+ if [ -f $CONNTRACKD_LOCK ]
+ then
+ logger "WARNING: conntrackd was not cleanly stopped."
+ logger "If you suspect that it has crashed:"
+ logger "1) Enable coredumps"
+ logger "2) Try to reproduce the problem"
+ logger "3) Post the coredump to netfilter-devel@vger.kernel.org"
+ rm -f $CONNTRACKD_LOCK
+ fi
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -d
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: cannot launch conntrackd"
+ exit 1
+ fi
+ fi
+ #
+ # shorten kernel conntrack timers to remove the zombie entries.
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -t
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -t"
+ fi
+
+ #
+ # request resynchronization with master firewall replica (if any)
+ # Note: this does nothing in the alarm approach.
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -n
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -n"
+ fi
+ ;;
+ fault)
+ #
+ # shorten kernel conntrack timers to remove the zombie entries.
+ #
+ $CONNTRACKD_BIN -C $CONNTRACKD_CONFIG -t
+ if [ $? -eq 1 ]
+ then
+ logger "ERROR: failed to invoke conntrackd -t"
+ fi
+ ;;
+ *)
+ logger "ERROR: unknown state transition"
+ echo "Usage: primary-backup.sh {primary|backup|fault}"
+ exit 1
+ ;;
+esac
+
+exit 0
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 09:21:52 +0000