Loopback Interface
- A Loopback Interface is a virtual interface on a network device that is used to communicate with itself.
- Primarily used for diagnostics and troubleshooting to ensure other processes and protocols are working.
- Often they are used on networking devices to ensure there is an IP address that is unique to that device, and not dependent on an active link, for management purposes
- In Dynamic Routing Protocols like OSPF, it can be used when deciding router priority or identification
- Example addresses are often 1.1.1.1, 2.2.2.2, etc., but these are real addresses on the internet and should not be used
- A better example might be 10.255.0.1, 10.255.0.2, etc.
- This is not the same as Loopback addresses, which are defined in RFC 1918 with the range 127.0.0.0/8, reserved block from Class A
OSI or TCP/IP Layer
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