If you notice the Exim graphs on your server have stop updating, you might want to check /var/log/munin/munin-node.log and see if you have lots of these entries:
tail /var/log/munin/munin-node.log ... Plugin "exim_mailstats" exited with status 768. ---- ...
You just need to remove the state file, and the graph will start updating again. Don’t worry about deleting the file, no data should be lost.
rm /var/lib/munin/plugin-state/plugin-exim_mailstats.state
We have a few cPanel servers deployed and to visually monitor performance we use the Munin monitoring tool. We were having issues where the MySQL graphs would stop updating. The bug has to do with one of the perl libraries the script uses, which causes the MySQL plugin to have problems location the mysqladmin program.
To fix these, create or edit the following file:
vi /etc/munin/plugin-conf.d/cpanel.conf
It should contain the following:
[mysql*] user root group wheel env.mysqladmin /usr/bin/mysqladmin env.mysqlopts --defaults-extra-file=/root/.my.cnf
This would load the username and password from root’s mysql config. If that file doesn’t exist you can create it:
sudo vi /root/.my.cnf
[client] user="root" pass="secret!password"
Now just restart Munin, wait a a little bit, and the graphs should start populating again!
sudo /etc/init.d/munin-node restart
