NF Deregistration Trigger Events Call Flow
This section describes the NF deregistration trigger events call flow.

Step | Description |
---|---|
On startup | |
1 | The SMF rest-ep registers for topology manager events to identify the state of other rest-ep instances and keeps a track of these instances in an instance state database. |
2 | The SMF rest-ep registers for the termination handler with the application infrastructure for receiving notification when the application infrastructure stops functioning. As part of the termination handler, the SMF rest-ep monitors the instance state database for any other working rest-ep. |
3 | The SMF rest-ep starts the topology event. |
4 | The SMF rest-ep saves the status of other rest-ep replicas in the instance state database. |
When the N11 and SBI endpoints are offline | |
5 | The SMF rest-ep sends the Handle NF deregister message to the NRF-Lib. |
6 | When all the SBI and N11 VIP IP endpoints are offline, the SMF rest-ep sends the deregistration request to the NRF. |
7 | The NRF sends the NF deregister response to the NRF-Lib. |
8 | The NRF-Lib resets all the management information that is configured in the cache pod. |
When no SBI endpoint exists | |
9 | The SMF rest-ep starts the topology event to stop the other rest-ep. |
10 | The SMF rest-ep starts the termination handler callback. |
11 | The SMF rest-ep checks the instance status database for any other working rest-ep. |
When no rest-ep is functional | |
12 | The SMF rest-ep sends the Handle NF deregister message to the NRF-Lib. |
13 | The SMF rest-ep sends the deregistration request to the NRF. |
14 | The NRF sends the NF deregistration response to the NRF-Lib. |
15 | The NRF-Lib resets all the management information that is configured in the cache pod. |