Trunked port in router and MTU

Unanswered Question

I need to adjust the MTU between two routers because of two encryptors in the path between the routers. The router ports are defined as 802.1Q trunked ports. The encryptor only processes layer 2 data smaller than 1420 bytes. can I use the IP mtu command in the router on a trunked interface?

I have this problem too.
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vishwancc Thu, 08/30/2007 - 13:23

As far as i know you can do it .

but it should be

conf t

- interface

- ip tcp adjust-mss 1200

For truncks that are in between two Cisco 3750 switches, is there a way to do the same thing?

sample switch config:

interface FastEthernet1/0/33

description Trunk Connection via IPSEC INE

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 1,6,58,59,222,1002-1005

switchport mode trunk

speed 10

duplex full

spanning-tree port-priority 240

spanning-tree cost 5000

no shut


nambi_gct Fri, 08/31/2007 - 00:01

Mike,you can use "mtu " command to do this.IP MTU by default is adjusted according to MTU of the physical interface.if you need mtu size greater than 1500 please enable jumbo settings with "system jumbomtu" command."ip mtu" command on l2 interface is not meaningful.


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