Event retrieval

When the probe is running, it receives events from the NNMi system as they are generated. The probe receives details of new incident events and updates to existing events that match the criteria in the SubscriptionFilter property.

Each message from the NNMi system contains a $Resent, $Identifier and $UpdateTime element. These elements indicate whether the message is new, an update to a previous message, or if the message has previously been processed by the probe.

For existing events, the probe receives notification only if either the $LifecycleState or $RcaState element of the incident is updated.

The probe maintains an internal cache of events it has received. The probe uses this cache to avoid sending false duplicate events to the Netcool/OMNIbus event list.

The NNMi system can detect if a message has not been sent, and makes three attempts to resend the message before it is discarded.