Troubleshooting

See also FAQ_no_graphs

This page lists some general troubleshooting for Munin.

  • 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
  • Is the munin-node process running on the agent node?
  • Does it allow your munin server to contact it? (Hint: check the "allow" directive in munin-node.conf)
  • Try to telnet to the host where you run munin-node (127.0.0.1 or localhost if Munin server process 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 [...]
    
  • Do the dirs 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)

See also FAQ_no_graphs