Uses of Loopback Interface
- It is used for routing protocols, reachability, and testing purposes.
- It is also used to identify the device while physical ports can also be used to identify the device loopback interface are preferred.
- Protocols like OSPF also use the loopback interface to determine their properties
Configuring a Loopback Interface in Cisco
A loopback interface is used for device identification. Although you can use any interface address to determine if the device is online, we recommend using the loopback address. Network topology changes can remove interfaces or change addresses, but the loopback address never changes.