You can configure the vCenter Hyperic server to throttle back alert notifications in the event of an alert storm.

You configure the maximum number of notifications that Hyperic will issue within a fifteen second interval. When the threshold is reached, vCenter Hyperic stops sending individual alert notifications, and instead, sends a summary of alert activity to designated recipients every ten minutes. When the volume of notifications falls below the specified threshold, vCenter Hyperic resumes sending individual notifications.

Notification throttling is disabled by default. You configure it on the Server Settings page, available from the Administration tab.