Health Check Software

my company has been using PRTG, its free for up to so many "probes" but this software is fantastic. We use it to monitor just about everything imaginable. It Pings, it gives hardware status, CPU usage, RAM usage whatever you want to configure it for. It will also send out alerts when devices become unresponsive. I highly recommend it. 

https://www.paessler.com/prtg

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I should mention it gives you a historical perspective too so you can see hard drive capacity over a years time, average ping responses, bandwidth utilization across routers, and set alerts based on abnormal conditions. It can be a bit pricey but we have been using it for over a year and its worth every cent, especially knowing when a server goes down, or even a service on the server. 

Related: Network Monitoring / SNMP for Video Surveillance Guide

We also use PRTG and it is really good at monitoring, logging and alerting you when things break or exceed thresholds it does not give you a way to fix the issue.   We now use RMM software that allows us to receive alert and right from the alert we can remote connect to the server, IP camera, switch, AP, UPS.   This has helped make our support more efficient as we no longer have to get an alert from PRTG then get access via Teamviewer or SSH to fix the issue. 

Michael, care to share the name of this RMM software which allows you to remotely fix devices? 

PRTG is a great option. I'm also fond of PulseWay. It allows you to monitor cpu and ram levels, ping response times, whether or not specific services are running, whether or not specific TCP ports locally or remote are reachable, it has some SQL monitoring capability, is extensible, and has mobile and dashboard applications for monitoring.

It used to be that it was free up to 3-5 servers, but I don't think they have a free tier anymore. It's still surprisingly affordable though, and they also have an enterprise tier for systems which are airgapped where you would run your own monitoring server in addition to the agents.