nrpe check_smtp & check_mysql notes

4.12pm. Today I have been playing with nagios plugins that allow me to monitor every service on my development box (Sherpa).

NB: These are local NRPE based checks (the daemon only runs on localhost).

* 'check_smtp' is setup by installing 'nagios-plugins-smtp.x86_64' and then monitored by nrpe by adding the following command to the '/etc/nagios/nrpe.cfg' file.

command[check_smtp]=/usr/lib64/nagios/plugins/check_smtp -H localhost

I can then check this from my NetworkMonitor box via:

# /usr/lib64/nagios/plugins/check_nrpe -H sherpa -c check_smtp
SMTP OK - 0.013 sec. response time|time=0.013064s;;;0.000000

* 'check_mysql' is a little more difficult as it requires a new MySQL user to be created, but easily done. Again we install 'nagios-plugins-mysql.x86_64' but have to be perform the following before editing the '/etc/nagios/nrpe.cfg' file.

# mysql -u xxxxx -p
mysql> CREATE USER 'nrpe'@'localhost' IDENTIFIED BY '*****';
mysql> exit

Now we can test the command locally via:

# /usr/lib64/nagios/plugins/check_mysql -H localhost -u nrpe -p *****

or just add the following to the nrpe.cfg file.

command[check_mysql]=/usr/lib64/nagios/plugins/check_mysql -H localhost -u nrpe -p *****

Dont forget to restart the local nrpe service(!).

Now onto adding the service templates on our Nagios box:

define service{
use generic-service
host_name Sherpa.xxxxxxxxxxxx
service_description postfix SMTP Service Check
check_command check_nrpe!check_smtp
}
define service{
use generic-service
host_name Sherpa.xxxxxxxxxxxx
service_description MySQLd Service Check
check_command check_nrpe!check_mysql
}

reload nagios, job done.