SRP Loopback Interface
SRP loopback interface is the loopback interface for Service IP (N3) or Next-hop IP for IP-Pools (N6). The IP addresses of these loopback interfaces must be on the same subnet as the ethernet interfaces of the context. The SRP loopback interfaces have the same IP address on both Active and Standby UPFs.
-
When UPF is Standby, SRP loopback interfaces will not send ARP reply or GARP packets. For IPv6, the UPF does not respond with the Solicited or the Unsolicited Neighbor Advertisement message.
-
When UPF is Standby, SRP loopback interfaces are enabled with an IP address attached inside boxer so that the UPF services bound to these interfaces remain in running state.
-
When UPF transitions from any other state to the Active state, the SRP loopback interfaces send out GARP packets. For IPv6, the UPF sends Unsolicited Neighbor Advertisement messages.
The following figure illustrates the 3RU wiring diagram for non-bonded interfaces.
