Installing Nagios’ NRPE on AIX

Today I installed NRPE on approximately a dozen AIX servers, and I was surprised not to see a solid HOWTO on the net. Not being an AIX admin, I had a little difficult and had to ask others about AIX-ish way of doing things, but for those familiar with “old school” ways of doing things, it should be fairly straight forward. Here is a quick overview of that process (I put a more detailed HOWTO on NagiosWiki and am hoping others add to it)

(1) grab the pre-compiled binary, unzip, and then untar it in the /opt directory, which is where many admins like to store large packages.

cd /opt
wget http://www.domain.com/path/to/nrpe-nsca-plugins.tgz
gunzip /opt/nrpe-nsca-plugins.tgz
tar xvf /opt/nrpe-nsca-plugins.tar

(those who’d like to simply look at the contents of the tar can type tar tvf)

(2) Now grab and configure the /etc/ files. Some admins (like myself) like all the /etc/ config files to be in one location.

cp /opt/nagios/etc/* /etc/

OR log on another similar box and type in the following to push it over to this box

scp nrpe.cfg root@otherbox:/etc

OR grab nrpe.cfg from another box and copy to your /etc directory

scp root@otherbox:/etc/nrpe.cfg /etc/

(3) modify the NRPE handlers in nrpe.cfg to include the correct path to the binaries you gunzip’d and untar’d in /opt

command[check_users]=/opt/nagios/libexec/check_users -w 5 -c 10

(4) now, add Nagios’ NRPE to the /etc/rc.local for each reboot

nohup /usr/bin/nrpe -c /etc/nrpe.cfg -d

(5) Now, start the NRPE service and associate it with the /etc/nrpe.cfg file you cp’d over

/usr/bin/nrpe -c /etc/nrpe.cfg -d

(6) Now, double check everything to make sure it’s all working. That includes: (a) checking the running processes on your AIX server, (b) checking the rc.local file on your AIX server, and also (c) making sure that your Nagios server can access the AIX server using its check_nrpe plugin. If there is a problem, try tail-ing the syslog for clues (tail /var/adm/syslog)

less /etc/rc.local
nohup /usr/bin/nrpe -c /etc/nrpe.cfg -d > /dev/null 2>&1 #Start NRPE for Nagios

AND

ps -ef | grep nrpe
root 458886 589858 0 01:11:51 pts/0 0:00 grep nrpe
nagios 536778 1 0 01:11:13 - 0:00 /usr/bin/nrpe -c /etc/nrpe.cfg -d

From Nagios (this was on my CentOS 4.x box)

cd /usr/lib/nagios/plugins/
./check_nrpe -H AIX_Server -c check_whatever
(RETURN OK)