Comment by otterpro
I recommend [librenms/librenms: Community-based GPL-licensed network monitoring system](https://github.com/librenms/librenms), which is Open source and free.
I recommend [librenms/librenms: Community-based GPL-licensed network monitoring system](https://github.com/librenms/librenms), which is Open source and free.
Does that mean that it has a library of devices so that it knows what SNMP stuff from them means? (I barely know how SNMP works).
Yes. That's called SNMP MIBs, and LibreNMS has a lot of the standard/well known device MIBs to parse out the details.
https://docs.librenms.org/Support/FAQ/#how-does-librenms-use...
...and good, too.
In the default mode, all you have to do for configuration is tell it the names or IPs of things to monitor and an SNMP community string. It scans for every tree that it understands, and will rescan occasionally.