I'm looking for a good web based portal to install on internal production servers to give information about the health of the server to people who have no login permission for that server at the command line. Typical information would be disk capacity left, processes running status, capacity graphs for network, disk and CPU.
Ideally, the portal would support installation on both Linux and Windows servers.
Nagios is an excellent tool for that job. It can provide you both health status for practically anything and graphing. It can monitor Linux, Windows, and lots of typical services you have.
Have not ever installed it on Windows, though.