GBIC 1000 Base LX and GLC-LH-SM problem

[MOREAU_Julien]

Hy,

I have a problem with different GBIC :

I have ordered 10 : GLC-LH-SM (LX/LH) GBIC for my customer. I have 5 links between 4503 and 2960G with Single Mode Fiber (patch cord in SMF too). Only 3 link are working properly.

In wrong link :

I have tried to change GBIC (with all GLC-LH-SM) and it's the same problem.

I have tried with 2 GBIC 1000 Base LX (LX only) and the link works properly.

Here, different tests results :

GLC-LH-SM with GLC-LH-SM ==> Link down

GLC-LH-SM with 1000 Base LX => Link down

1000 Base LX with 1000 Base LX => Link up !

There is no difference between all link (same switch's configuration, same kind of fiber and patch cord) execept maybe the distance (but not much).

Someone have any idea ?

Thanks for your answer.

Julien

[Tom Randstrom]

Have you been able to verify that the 4 remaining LX/LH transceivers are operational.... by swapping them into the links that are presently working with LX/LH transceivers?  This will verify for non functioning transceivers.

If I understand you correctly, you have verified that all the Singlemode fibers you are planning on using are good because you can send a signal across each pair using a pair of LX transceivers?

Is there any LINK LED when the LX?LH transceivers are used (on the non-functioning link)? A test you might run is to install a LX/LH transceiver in a switch at one end and then,at the other end, loop it back at the patch panel.  This will check to see if you get link back. 

What are the Show Interfaces and Show Interfaces Transceiver commands showing when the Switches have the LX/LH transceivers installed (in a working link and a non working link?

You might try to issue a No Autonegociation command on the ports that are not functioning and a No Duplex command.  Then Shut/No Shut.  See if that brings them online.  If not, then manually set the speed and duplex settings.

Another interesting situation....

Tom

[MOREAU_Julien]

Have you been able to verify that the 4 remaining LX/LH transceivers are  operational.... by swapping them into the links that are presently  working with LX/LH transceivers?  This will verify for non functioning  transceivers.

Yes I have tried and those 4 GBIC are working properly.

If I understand you correctly, you have verified that all the Singlemode fibers you are planning on using are good because you  can send asignal across each pair using a pair of LX transceivers?

Yes.

Is there any LINK LED when the LX?LH transceivers are used (on the  non-functioning link)? A test you might run is to install a LX/LH  transceiver in a switch at one end and then,at the other end, loop it  back at the patch panel.  This will check to see if you get link back.

No in each side, ports were not connected

What are the Show Interfaces and Show Interfaces Transceiver commands  showing when the Switches have the LX/LH transceivers installed (in a  working link and a non working link?

I will try asking my custormers to do it.

You might try to issue a No Autonegociation command on the ports that  are not functioning and a No Duplex command.  Then Shut/No Shut.  See if  that brings them online.  If not, then manually set the speed and  duplex settings.

I will try too.

Thanks

I will come back when if I solve the problem

[MOREAU_Julien]

Hy,

I have find the problem. The SMF was very durty...

Maybe 1000base LX are less sensible than GLC-LH-SM.

Thanks for all.