LinuxHostingSupport

Munin plugin is known to have issues while generating Mysql graphs. The mysql graph remains empty due to a bug in the Perl library that causes the path to the mysqladmin to be lost.

The solution is to specify the path to mysqladmin in the /etc/munin/plugin-conf.d/cpanel.conf file. Edit the file

# nano /etc/munin/plugin-conf.d/cpanel.conf

and add the below line in the [mysql*] section

env.mysqladmin /usr/bin/mysqladmin

The mysql section should look like follows

[mysql*]
user root
group wheel
env.mysqladmin /usr/bin/mysqladmin

Restart the munin-node  service and see if it works. If it doesn’t, it indicates munin cannot read the values of mysql variables i.e. the username/password of mysql.

In such a case, have munin read the Mysql password from the .my.cnf file directly which is residing under the /root directory. To achieve this, create a file say, /root/mysqlpass

# nano /root/mysqlpass

and add the following command

/usr/bin/mysqladmin -uroot -p`cat /root/.my.cnf | grep pass \
| sed s/pass// | sed s/=// | sed s/\"//g` $@

The sed command may look confusing but it just removes words and characters around the password.

Set executable permission on the file

# chmod 755 /root/mysqlpass

Now edit the /etc/munin/plugin-conf.d/cpanel.conf file again and replace

env.mysqladmin /usr/bin/mysqladmin

with

env.mysqladmin /root/mysqlpass

Once done, restart the munin-node service and munin will start generating the Mysql graphs