Noob here (WRT Nagios, been managing my Linux hosts for decades now.) I'm just starting to deploy Nagios Core to monitor stuff on my home LAN that I'm getting tired of doing manually (and with the fear that I'll overlook something that will hurt.) Here are some of the things I'd like to watch:
- HDD/SSD status as revealed by SMART data
- Filesystem parameters such as capacity, RAID issues and so on. (I'm using ZFS on my file server and laptop and desktop.)
- Problems such as excessive processor/RAM use.
- Problems such as a host that goes AWOL. In this regard I have a handful of Raspberry Pi Zeroes monitoring sensors for stuff like temperature, humidity and so on. I've implemented MQTT Last Will and Testament to monitor their presence on my LAN but that means I have to check a page on my Home Assistant setup to see if they're all still there and reporting.
- I'd consider monitoring some WiFi light bulbs and outlets since the App frequently tells me they're not available when I know they are.
The first thing I ran across was NRPE. There is a package in the Debian and R-Pi OS repos for NRPE. But one of the documentation pages lists it as deprecated. Other documentation does not. If it is deprecated, I should probably go with something else, like NCPA.
There is no package in the Debian/R-PiOS repos with NCPA in the name. I can see where I can download a current package for Debian, but packages for R-Pi OS are not presently built because this project does not have access to a server running that OS. A further complication is that I'm using the 64 bit R-Pi OS on some hosts and I'm not sure if the older package will work for that. And IAC it is an OS release behind (Buster vs. Bullseye.) I guess I can build from source if I decide to go this way, assuming I did not run into any issues that I could not resolve. (I feel a little like I'm wading into the swamp here.)
There is a package in the Debian repos named nrpe-ng. I found the github repo for that and it has been archived, last update in 2017.
There is mention of using an SSH connection to access remote hosts and that seems like it would be another option.
I'm left wondering ...
- Is NREP truly deprecated or were pronouncements of imminent death premature?
- Is NCPA the way I should proceed?
- Or should I be looking at SSH for this?
- And what other questions should I be asking? (What are my unknown unknowns?)
Thanks!