MTU setting on FastEthernet

HI
Is it possibel to set MTU on Fastethernet ?
I was trying to change MTU on 7206 and i got this error
config-if)#ip mtu ?
<68-1500> MTU (bytes)
config-if)#mtu 1510
% Interface FastEthernet0/0 does not support user settable mtu.

Thank you . The RFC was so useful
And know i want to aks you
1. MPLS MTU command , should be on the Edge-LSR interface connected to MPLS clou or on the interface connected to CE ?
2.On section 3.4 of the RFC it says that :
4. If the IP datagram has the "Don't Fragment" bit set in its IP
header:
a. the datagram MUST NOT be forwarded
b. Create an ICMP Destination Unreachable Message:
i. set its Code field [3] to "Fragmentation Required and DF
Set",
ii. set its Next-Hop MTU field [4] to the difference between
the Effective Maximum Frame Payload Size and the value
of N
c. If possible, transmit the ICMP Destination Unreachable
Message to the source of the of the discarded datagram.
How can i do this
If the source who set DF is client , it will be easy , but what if a webserver is setting DF ? and also do not support path Mtu discover ?
regards

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??
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exe78 wrote:
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Robbie wrote:
I have been reading the SINET BT documents which state MTU should be set at 1500:
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The Internet is a complex system isn't it, held together by a multitude of committed technicians.
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Ethernet v2 1500[3] Nearly all IP over Ethernet implementations use the Ethernet V2 frame format.
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"I have this awful feeling someone is watching every move I make (one of my pet hates is router location tagging)." Marvin (A paranoid Android)

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Solved!
Go to Solution.

MTU IS 1500 by default
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Internet sharing requires special MTU setting in n...

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MTU setting on FastEthernet

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