2950 Question

[linux00]

Ok, I have a 2950 Series switch and I think one of the Gigabit ports has failed gig0/2. What is the command to set a loopback test on that interface??? Thanks

 

[burtsbees]

It automatically performs a loopback test on all ports (internal) when it boots up. Just watch it after you turn it off/back on. Is this switch in production? What indication do you have that it's bad?

Burt

 

[linux00]

This switch is in production, that will be one reason why I cannot restart the switch. The main indication is that the switch was getting the fiber feed on gig0/2 and working fine, until two days ago when no link was seen... I configure gig0/1 and swapped the fiber to that port and boom switch back in business... I believe there is a command to set the port to loopback and that way you can identify if the port is bad.. correct me if i am wrong

 

[burtsbees]

Are you using both of these ports as trunks? If so, and spanning-tree is in use, it could be blocking one port.

Burt

 

[linux00]

yes both setup for trunking and yes spanning-tree enabled... back to the original question... I was told that you could loop back the interface to see if it goes up and down or if it stays up then the gigabit port is good... can anybody help on how to configure the port for loopback testing???

 

[burtsbees]

Wire Gigabit port one to Gigabit port two. Does the link come up? If so, the port is good. STP blocks on the port and prevents any loops (port one receive (RX) goes to port two transmit (TX), and port one TX goes to port two RX).
Or, wire the Rx to the Tx of the same port.

Burt