Interface loopbacks

[scott.willett]

I work for a telco and we have all kinds of Cisco devices.

Does anyone know why some models have the interface loopback option for "local" and "remote loops", and some do not??

Scott

Example:  Local loop

Conf t

int gi1/8

loopback local

end

[Bilal Nawaz]

I think its used to isolate a failing of a T1 / E1 etc....

Maybe command is supported on certain types of devices or IOS, like code or devices e.g. that support voice vs a code that supports L2 switching only.

http://www.cisco.com/c/en/us/support/docs/voice/device-signaling/116492-trouble-t1e1-00.html#anc3

[scott.willett]

Bilal,

I was thinking that the loopback feature is only allowed on certain model and IOS as well.  Just wanted to see if anyone could confirm.  

I specifically am looking to loop Ethernet interfaces to clear ports.

Thanks,

Scott