Quick ? regarding loopback addresses...

[getwithrob]

What device types are generally configured w/ loopback interfaces/addresses and which aren't?

rtrs, fixed port switches, term servers, modular switches, modular switches w/ routing capability or a modular switch w/ an MSFC daughter card doing the lan routing?, etc.

I don't think a device like a 24 port 3550 fixed port switch is even configured with a loopback interface. As a matter of fact it and maybe other device types or versions of code may not allow loopbacks to even be configured.

Any input would be appreciated....

[spremkumar · Accepted solution]

Hi

You wont be able to configure loopback interfaces on a Layer 2 Switch.

Loopback interfaces are generally created in devices such as routers and L3 switches so that it can be made as the device id when you have routing protocols configured in them.

Also the loopback interfaces are logical interfaces and dont carry any traffic.

While configurined GRE tunnels you can have loopback interface configured and have your tunnel ip configured or tunnel source ip configured..

regds