Is it possible to install gKrellM on OPNsense?
It would be nice, so I can remotly monitor the firewall in a simple way (Temperatures etc).
gKrellM is the only x-plattform applikation, that I have found, that can do this over the network.
I would recommend against that, because you need a heck of a lot of libraries on which X applications depend.
What about an NMS like Observium (https://www.observium.org) or LibreNMS (https://www.librenms.org)?
In case you are interested: you can install Observium on any FreeBSD host or VM following my instructions (https://github.com/pmhausen/observium-freebsd-install). Not directly on OPNsense, of course.