Hello,
Real-Time Alarms shows all alarms which have not been recovered with the respective Recover button, or automatically by receiving an SNMP Trap or Polling detection that indicates the issue is resolved. For example a link that goes down will show in Real-Time Alarms until an SNMP Trap is received that indicates the link is UP again, or until IMC's built-in polling detects the interface is UP.
Polling only happens in set intervals and isn't nearly as quick as SNMP Traps, which are sent whenever the event happens on the device. Considering your situation, it's likely you only have polling enabled by default, and need to configure traps if you want alarms like link up/down to be recovered in real-time.
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Justin Guse
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