3750 PoE problems

Unanswered Question
Jun 24th, 2008

Hi ,

I'm currently installing a couple of 3750 on a new building. Swicthes have to connect to Avaya's IP phones. Connected at 100 Mbps full duplex phones work OK, but whwn conected at 1000 Mbps (1Gbps) port, throuhg an 1Giga adapter provided by Avaya for phones, some phones are unable to connect to switch port (which remains down/down) an a few of them do not power up.

I have tried any combination on switch &phones autonegatioation and fixing speed and duplex. I ahve also checked cabling.

We get always the same results.

Is there any known issues between these kind of phones and 3750 switches?

Thx for ideas

I have this problem too.
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glen.grant Tue, 06/24/2008 - 03:47

If some of them are working at 1000 mbps then I doubt its the switch . I would look at your cabling , patches etc... Gigabit takes all 8 wires to run and you can cannot have a bad pair anywhere in the link whether it be patches or the house wiring itself . We have Avaya phones working at a gig just fine using 3750 power. Leave the speed/duplex at auto for gig speeds.


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