Troubleshooting

See also FAQ_no_graphs

This page lists some general troubleshooting for Munin. The examples show a munin-node agent running on 127.0.0.1; replace with other IP adresses as you see fit.

• Is the munin-node process running on the agent node?

• Did you restart the munin-node process?

• Does the munin-node agent allow your munin master to contact it? Simple test: telnet localhost 4949 Hint: check the "allow" directive in munin-node.conf. Make sure any firewalls allow contact on destination port 4949.

• Try to telnet to the host where you run munin-node (127.0.0.1 or localhost if Munin master and munin-node is on the same system) on port 4949. The prompt should look something like this:

  # telnet localhost 4949
  Trying 127.0.0.1...
  Connected to localhost.
  Escape character is '^]'.
  # munin node at [your server name]
  

• Does the above output give the same hostname should be expected in munin.conf? E.g. if munin.conf has the following entry:

  [foo.example.com]
    address foo.example.com
  

  ...then telneting to the node should give you:

  # munin node at foo.example.com
  

  In particular, note that if you have fully qualified domain name (FQDN) in munin.conf, the server you're monitoring have to identify itself with FQDN as well.

• Does munin-node recognize any plugins? Try issuing the command list after telneting to the agent, and a (long) list of plugins should show.

  # telnet localhost 4949
  Trying 127.0.0.1...
  Connected to localhost.
  Escape character is '^]'.
  # munin node at foo.example.com
  list
  open_inodes irqstats if_eth0 df uptime [...]
  

• If you're troubleshooting one particular plugin, test it on the agent with the command munin-run [plugin_name].

• Do the directories specified by dbdir, htmldir, logdir and rundir have the correct permissions? (If you first ran munin as root, maybe they're not readable/writeable by the user that runs the cron job)

• Is munin-cron established as a cron controlled process, run as the Munin user?

• Does the output when running munin-update as the Munin user on the server node show any errors? Try running "munin-cron --debug > /tmp/munin-cron.debug" and checking the output file /tmp/munin-cron.debug

See also FAQ_no_graphs