Regular Expressions in Nagios
I am a massive fan of Nagios. Whilst it has an initial learning curve it can be an incredibly powerful system. Assuming you have a standardised naming structure for your servers, switches and other infrastructure you can use regular expressions to create a hostgroup that will cover all your devices.
define hostgroup { hostgroup_name Domain Controllers alias All Domain Controllers members ^.*dc[0-5]$,^.*(dev|prd|)$ } |
If you run a logical structure and have lots of switches or servers this can be a really easy way to ensure you are monitoring all servers or switches and can easily be expanded by simply changing the regex.