We currently have a few servers, 1 WHM VPS (2GB), 1 MS SQL VPS (2 GB), and 1 IIS VPS (2GB). The VPS servers are doing fine as far as uptime and response times but we would like to add the following features.

1) monitoring with load statistics 2) failover

I have looked a Zabbix, Zenoss, Nagios, and a couple of other cloud solutions like monitor.us and watchdog from Zerigo. Ideally for the monitoring solution.

Our current hosting company suggested we get a dedicated server or VPS and install load balancing software (not sure I like that idea).

I've looked into Rackspace and Amazon load balancers which seem like the most feasible solutions for load balancers.

Does anybody have any input on the monitoring and load balancing products I'm looking into?

Monitoring should monitor uptime as well as give reports on memory usage, disk usage, processor usage, and which processes/websites/users are responsible for the load.

It would be ideal if the load balancer worked with any IP. Not sure if either Rackspace or Amazon load balancers would allow load balancing with servers outside their datacenter.

Thank you.