Alerting on Server Reboot

[PNIXON (at) ci.somerville.ma.us]

Hey all,
 Does anyone have a recommended solution for triggering an alert when a
server is rebooted?

 Assuming it comes back up within the ping cycle, the conn test still
passes.

 I'm aware that the CPU turns yellow due to the reboot, but is it possible
to build an alert rule to trigger on ServerX CPU = Yellow?

Thanks for any feedback...

--Pat