Hi, i have an old nagios server with 200 hosts and 1500 services, and plan to add another box (because of performance issues).
Any advice about what hardware to choose? It seems nagios is not very processor intensive, top gives me like 2-3% processor utilization at most. SATA disk or SCSI? How much RAM should i go for?
if you use 2 servers they can check each other so no need for big redundant stuff. 
For what i’ve seen you can run nagios on almost everything… Here it’s a Sun with LOTS of RAM but there’s other stuff on it and nagios takes really only a little part…
Luca