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#
# 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
#
# Entries committed to the connection tracking table
# starts with a limited timeout of N seconds until the
# takeover process is completed.
#
CommitTimeout 180
#
# 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
}
#
# 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.
#
McastSndSocketBuffer 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.
#
McastRcvSocketBuffer 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
}
}
#
# General settings
#
General {
#
# Number of buckets in the caches: hash table.
#
HashSize 16384
#
# Maximum number of conntracks:
# it must be >= $ cat /proc/sys/net/ipv4/netfilter/ip_conntrack_max
#
HashLimit 65536
#
# 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.
#
SocketBufferSize 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.
#
SocketBufferSizeMaxGrowth 8388608
#
# 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
# }
}
}
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