If you have setup munin-node on a cPanel server it’s possible that your MySQL graphs stop updating at sometime, or don’t even generate from the beginning.
To fix, edit the following file:
/etc/munin/plugin-conf.d/cpanel.conf
And make sure that the mysql section contains the following:
[mysql*]
user root
group wheel
env.mysqladmin /usr/bin/mysqladmin
env.mysqlopts --defaults-extra-file=/root/.my.cnf
In newer MySQL versions, if you have InnoDB disabled, Munin will fail to run giving you the following error:
root@myserver [~]# munin-run mysql_connections DBD::mysql::st execute failed: Unknown table engine 'INNODB' at /etc/munin/plugins/mysql_connections line 958.
This is caused because the error message is changing between versions and the mysql_ plugin for munin hasn’t been updated in order to recognize it.
The fix is pretty simple, just open /usr/share/munin/plugins/mysql_ with vim on line 958 (hint: vim +958 filename) and replace as bellow.
Original code
if ($@) {
if ($@ =~ /Cannot call SHOW INNODB STATUS because skip-innodb is defined/) {
$data->{_innodb_disabled} = 1;
return;
}
die $@;Fixed code
if ($@) {
if ($@ =~ /Unknown table engine 'INNODB'|Unknown storage engine 'innodb'|Cannot call SHOW INNODB STATUS because skip-innodb is defined/i) {
$data->{_innodb_disabled} = 1;
return;
}
die $@;Save the file and you’re good to go 🙂
Last night I attempted to get named monitoring working with Munin on my two cPanel DNS Only boxes. Named is actually the most important service to monitor on a DNS Only box so in my opinion it should be enabled by default when you install Munin via WHM.
The whole process was actually really straightforward and the only thing I had to do was to apply a set of Debian instructions I found here, on CentOS. Here’s how you can install Munin and setup named monitoring Continue reading