I need a service that monitors servers when at times there could be a heavy load and has as many features that are needed as possible. Any recommendations? I'd like to know for example if there are too many connections and site can't handle it, any outages etc.
So you mean something that runs on your server? That's the only way you'll get a connection count as far as I know.
I was thinking you meant a monitoring service like Pingdom or Basic State, but I gather that's not what you're after?
Yeah, if it's uptime monitoring you're looking for:
The good one:
https://www.pingdom.com/
The local one with limited functions:
http://www.sitebeak.com/
I personally like PRTG, run it on a local always-on pc. It will monitor up to 10 sites for free 20 if you give them a link somewhere. 100 for $400, last time I priced it.
I've set it up to email me if a site is down more than 5 minutes, and texts me if it's down more than 1 hour. I've weeded out bad shared hosts easily just from long term reports and always find out problems right away. It shows connect time, speed, etc. so it's much more than just an up/down monitor.
Starting with PRTG and will probably roll out pingdom also. Thanks for the help/