Full duplex with a 100 FX connection

Unanswered Question
Nov 1st, 2007
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I have a WS-2960-24TC-L running with c2960-lanbase-mz.122-40.SE.bin with two GLC-GE-100FX= in it.

I am trying to link this switch to a 3750 with a GLC-GE-100FX= and a WS-2955C-12.

The 2960 always auto negotiate to 100 half with both switches. In the 3750 I can force the port to Full duplex but the DUPLEX command in not ava lable on gig 0/1-2.

I would be nice to have a 100 Full link between the switches.

Can you help me ?

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sstudsdahl Thu, 11/01/2007 - 14:56
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What are your ports configured like on the 3750 and the 2955? Try setting each side for autonegotiate. This should bring the connection up at 100/full.


scottmac Thu, 11/01/2007 - 16:07
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Current GigE is full-duplex only.

You might try using a 10/100 port (as a trunk port if necessary).

You can also try another cable, preferably a commercially made cable in good condition. Poorly terminated hand-made cables, or cables that have been kinked, stretched, crushed {etc} can cause the ports to downshift.

Good Luck



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