MTU limitation on Fastehernet ports on Cisco Routers

Branimir Turk · ‎04-05-2007

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).

Tnx

ankbhasi · ‎04-05-2007

Hi Friend,

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

Regards,

Ankur

Branimir Turk · ‎04-05-2007

ip mtu does not allow me to set value greather than 1500

rais · ‎04-05-2007

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.

Thanks.