My LDAP server has a Nagios NRPE client service that reports the performance of the server to the host Nagios server. The services were reporting as errors on the Nagios console. So I had to debug the issue.
First, I searched Google for this but everything I tried did not help. basically I tried adding more items in the Before section of the nrpe.service file without avail.
I then looked for details of the service using the command:
systemctl status nrpe
The message was that service was loaded but not enabled, preset is enable. I was not sure what to do next. I looked up how to enable systemctl services at startup and so looked first at
systemctl is-enabled nrpe
The answer came as disabled. So now I was getting somewhere. I finally tried:
systemctl enable nrpe
Voila, on restart, the nrpe daemon was up and running…