Suggestion for System Monitoring Tool

We have AIX and RHEL. Need suggestion for system monitoring tool for AIX and RHEL. Free or paid is fine as I would like to compare. Thank you

Hi.

For lists of simple tools Google search for:
compare system monitoring linux OR unix
yielding 20M+ hits.

For a comparison of more complex tools:
Comparison of network monitoring systems - Wikipedia

which would include facilities like cacti, nagios, etc.

A useful read might be Network monitoring - Wikipedia

Good luck ... cheers, drl

thank you

My personal favourite is check_mk(free basic version and commercial extended version. It's a system built around nagios or another core).

Another top system which is widely appreciated is icinga 2. Very resource efficient and without knowing it too much it seems one of the most modern and capable systems. Fully Open Source. I never reviewed it myself. But if I do, maybe this will be my new favourite.

Bloonix seemed very nice too. Well worth a closer look.

Zabbix is another major player. I do not like it(ugly gui, check_mk seems a lot easier to use for me) but maybe you do.