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CDP-4-DUPLEX_MISMATCH errors

Unanswered Question
Mar 8th, 2004
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Hi All,


I am hoping for some help with a "duplex mismatch" problem I'm having.


I have 2 switches (a Catalyst WS-C2924M-XL with a WS-X2922-XL-V module, & a Catalyst WS-C1924C-EN) connected via fibre. The 2924 port is configured as "100/full" while the 1924 port is configured as "Full duplex-flow control".


I regularly get the folowing message in the 2924's log buffer:


%CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on FastEthernet2/1 (not half duplex), with JNR_LIB_SW A (half duplex).


Now as far as I can see both ends are configured for full duplex. If I configure the 1924's port to be "half duplex" the messages stop. Network performance is poor either way.


Can anyone tell me what's going wrong here, & how to fix it? Many thanks in advance for any help provided.


Cheers,

Dirk

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Georg Pauwen Tue, 03/09/2004 - 00:52
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Hello Dirk,


what happens if you change the settings on the 1924 port to duplex full instead of duplex full-flow-control ?


Regards,


GP

Anonymous (not verified) Tue, 03/09/2004 - 14:31
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Hi GP,


Unfortunately changing the 1924 port to "duplex full" makes no difference. Our 2924 is the main switch on our network, & it has 6 other switches (all Cisco 19xx & 29xx) linked via fibre to it. I am getting the same message on 2 other switches, both of which are 19xx.


I would love to be able to fix this as our network performance on these links is poor.


Cheers,

Dirk

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