A detailed answer to that is beyond the scope of an SF answer, but it seems reasonable to me to give you some pointers. The solution comes in two parts:
- What plugin to run on the remote machine, and
- How to run it on the remote machine.
2) is easy: it's NRPE, or possibly remote execution via ssh (
check_by_ssh), or perhaps SNMP (though I don't favour that).
1) is the hard bit, and it's not worth doing (2) until you've cracked (1). This involves finding a way to monitor these parameters on the remote machine, and sensors are a notoriously tricky, BIOS-dependent, standards-unaware, documentation-poor area of work.
So first find a simple command that runs on each machine that gives access to the hardware parameters you want to measure; this is likely to require a different tool on each different hardware platform. Then wrap it in NAGIOS plugin logic. Then call it via NRPE.
Edit: there are any number of NRPE HOWTOs out there; this one looks pretty good to me. But I'll repeat my warning, there's no real point getting the NRPE bit in place until you have the commands to interrogate your hardware ready-to-run, and wrapped in a NAGIOS-friendly wrapper.