Nagios plugins

• Nagios
• NRPE

Check the amount of disk space available.

Warning on 20% remaining, critical on 10% remaining, looking at path “/”:

check_disk -w 20% -c 10% -p /

Check the current system load average. The load average format is the same used by “uptime” and “w”.

• -w WLOAD1,WLOAD5,WLOAD15 - Exit with WARNING status if load average exceeds WLOADn
• -c CLOAD1,CLOAD5,CLOAD15 - Exit with CRITICAL status if load average exceed CLOADn
• -r - Divide the load averages by the number of CPUs (when possible)

check_load -r -w 2,1.5,1 -c 4,3,2

Check for running processes.

Some available arguments:

• -w [num]:[num] - warning for value in range
• -c [num]:[num] - critical warning for value in range
• -u <uid> - check for user ID
• -a <argument> - only check for processes with specified arguments
• -C <command> - only check for exact match of command, without path

OpenSSH

SSHD will have one proc for the master daemon, and one for each user login as well. So setting a minimal range of 1 will check if it is running at all:

check_procs -c 1: -u root -C sshd -a /usr/sbin/sshd

ntpd

check_procs -c 1: -u root -C ntpd -a /usr/sbin/ntpd

syslog-ng

check_procs -c 1: -u root -C syslog-ng -a /usr/sbin/syslog-ng

Check swap space.

Warn on 20% available remaining, critical on 10%:

check_swap -w 20% -c 10%