MTU limitation on Fastehernet ports on Cisco Routers

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Apr 5th, 2007
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Is the MTU limitation on Fastethernet ports on Cisco routers in hardware or in software.

I am trying to increase MTU size on FE port to avoid frengmentation of GRE packets exiting the interface but I get % Interface FastEthernet0/0 does not support user settable mtu.

Is there any workaround? Or is there any cisco router that supports changing MTU on Fastehernet ports (not Gigabitethernet).


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ankbhasi Thu, 04/05/2007 - 04:46
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Hi Friend,

Can you try changing the mtu value with "ip mtu" command?



rais Thu, 04/05/2007 - 04:48
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FE ports should be following 802.3u standard. I don't think it will take MTU longer than what standard calls for. Payload can be max 1500 bytes.



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