From 5bdbce69495e0811186b92e4eb320e71fc1ff622 Mon Sep 17 00:00:00 2001 From: Christian Poessinger Date: Wed, 3 Oct 2018 15:41:21 +0200 Subject: Add Troubleshooting chapter --- docs/ch16-troubleshooting.rst | 164 ++++++++++++++++++++++++++++++++++++++++++ docs/index.rst | 2 + 2 files changed, 166 insertions(+) create mode 100644 docs/ch16-troubleshooting.rst (limited to 'docs') diff --git a/docs/ch16-troubleshooting.rst b/docs/ch16-troubleshooting.rst new file mode 100644 index 00000000..47abab04 --- /dev/null +++ b/docs/ch16-troubleshooting.rst @@ -0,0 +1,164 @@ +Troubleshooting +=============== + +Sometimes things break or don't work as expected. This section describes +several troubleshooting tools provided by VyOS that can help when something +goes wrong. + +Basic Connectivity Verification +------------------------------- + +Verifying connectivity can be done with the familiar `ping` and `traceroute` +commands. The options for each are shown (the options for each command were +displayed using the built-in help as described in the `Command-Line Interface`_ +section and are omitted from the output here): + +.. code-block:: sh + + vyos@vyos:~$ ping + Possible completions: + Send Internet Control Message Protocol (ICMP) echo request + + + +Several options are available when more extensive troubleshooting is needed: + +.. code-block:: sh + + vyos@vyos:~$ ping 8.8.8.8 + Possible completions: + Execute the current command + adaptive Ping options + allow-broadcast + audible + bypass-route + count + deadline + flood + interface + interval + mark + no-loopback + numeric + pattern + quiet + record-route + size + timestamp + tos + ttl + verbose + +.. code-block:: sh + + vyos@vyos:~$ traceroute + Possible completions: + Track network path to specified node + + + ipv4 Track network path to + ipv6 Track network path to + +However, another tool, mtr_, is available which combines ping and traceroute +into a single tool. An example of its output is shown: + +.. code-block:: sh + + vyos@vyos:~$ mtr 10.62.212.12 + + My traceroute [v0.85] + vyos (0.0.0.0) + Keys: Help Display mode Restart statistics Order of fields quit + Packets Pings + Host Loss% Snt Last Avg Best Wrst StDev + 1. 10.11.110.4 0.0% 34 0.5 0.5 0.4 0.8 0.1 + 2. 10.62.255.184 0.0% 34 1.1 1.0 0.9 1.4 0.1 + 3. 10.62.255.71 0.0% 34 1.4 1.4 1.3 2.0 0.1 + 4. 10.62.212.12 0.0% 34 1.6 1.6 1.6 1.7 0.0 + +**NOTE:** The output of '''mtr''' consumes the screen and will replace your +command prompt. + +Several options are available for changing the display output. Press `h` to +invoke the built in help system. To quit, just press `q` and you'll be returned +to the VyOS command prompt. + +Monitoring Network Interfaces +----------------------------- + +It's possible to monitor network traffic, either at the flow level or protocol +level. This can be useful when troubleshooting a variety of protocols and +configurations. The following interface types can be monitored: + +.. code-block:: sh + + vyos@vyos:~$ monitor interfaces + Possible completions: + Execute the current command + bonding Monitor a bonding interface + bridge Monitor a bridge interface + ethernet Monitor a ethernet interface + loopback Monitor a loopback interface + openvpn Monitor an openvpn interface + pppoe Monitor pppoe interface + pseudo-ethernet + Monitor a pseudo-ethernet interface + tunnel Monitor a tunnel interface + vrrp Monitor a vrrp interface + vti Monitor a vti interface + wireless Monitor wireless interface + +To monitor traffic flows, issue the :code:`monitor interfaces flow` +command, replacing `` and `` with your desired interface type and +name, respectively. Output looks like the following: + +.. code-block:: sh + + 12.5Kb 25.0Kb 37.5Kb 50.0Kb 62.5Kb + ???????????????????????????????????????????????????????????????????????????????????????????????????? + 10.11.111.255 => 10.11.110.37 0b 0b 0b + <= 624b 749b 749b + 10.11.110.29 => 10.62.200.11 0b 198b 198b + <= 0b 356b 356b + 255.255.255.255 => 10.11.110.47 0b 0b 0b + <= 724b 145b 145b + 10.11.111.255 => 10.11.110.47 0b 0b 0b + <= 724b 145b 145b + 10.11.111.255 => 10.11.110.255 0b 0b 0b + <= 680b 136b 136b + ???????????????????????????????????????????????????????????????????????????????????????????????????? + TX: cumm: 26.7KB peak: 40.6Kb rates: 23.2Kb 21.4Kb 21.4Kb + RX: 67.5KB 63.6Kb 54.6Kb 54.0Kb 54.0Kb + TOTAL: 94.2KB 104Kb 77.8Kb 75.4Kb 75.4Kb + +Several options are available for changing the display output. Press `h` to +invoke the built in help system. To quit, just press `q` and you'll be returned +to the VyOS command prompt. + +To monitor interface traffic, issue the :code:`monitor interfaces +traffic` command, replacing `` and `` with your desired interface +type and name, respectively. This command invokes the familiar tshark_ utility +and the following options are available: + +.. code-block:: sh + + vyos@vyos:~$ monitor interfaces ethernet eth0 traffic + Possible completions: + Execute the current command + detail Monitor detailed traffic for the specified ethernet interface + filter Monitor filtered traffic for the specified ethernet interface + save Save monitored traffic to a file + unlimited Monitor traffic for the specified ethernet interface + +To quit monitoring, press `Ctrl-c` and you'll be returned to the VyOS command +prompt. The `detail` keyword provides verbose output of the traffic seen on +the monitored interface. The `filter` keyword accepts valid `PCAP filter +expressions`_, enclosed in single or double quotes (e.g. "port 25" or "port 161 +and udp"). The `save` keyword allows you to save the traffic dump to a file. +The `unlimited` keyword is used to specify that an unlimited number of packets +can be captured (by default, 1,000 packets are captured and you're returned to +the VyOS command prompt). + +.. _mtr: http://www.bitwizard.nl/mtr/ +.. _tshark: https://www.wireshark.org/docs/man-pages/tshark.html +.. _`PCAP filter expressions`: http://www.tcpdump.org/manpages/pcap-filter.7.html diff --git a/docs/index.rst b/docs/index.rst index 2875ca09..8fd6d15d 100644 --- a/docs/index.rst +++ b/docs/index.rst @@ -49,6 +49,8 @@ as a router and firewall platform for cloud deployments. .. include:: ch15-image-mgmt.rst +.. include:: ch16-troubleshooting.rst + Indices and tables ================== -- cgit v1.2.3