[c-nsp] cisco router 2800/3800 serie

[Flint, Chris]

12.4(20)T or newer should support the MTU change.  You still get the error message, but it does work.


Flint


-------------------------
Date: Wed, 26 Aug 2009 20:40:37 +0200
From: Peter Rathlev <peter at rathlev.dk>
To: Justin Shore <justin at justinshore.com>
Cc: "cisco-nsp at puck.nether.net" <cisco-nsp at puck.nether.net>
Subject: Re: [c-nsp] cisco router 2800/3800 serie
Message-ID: <1251312037.2932.36.camel at abehat.net.rm.dk>
Content-Type: text/plain

On Wed, 2009-08-26 at 13:00 -0500, Justin Shore wrote:
> I'm suspect that the interface MTU of the 1841 may not go above 1500.

It's even worse, it doesn't seem to support MTU != 1500 at all on the
built in FE interfaces.

Router(config-if)#do sh ip int bri
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            10.251.9.5      YES NVRAM  up                    up      
FastEthernet0/1            unassigned      YES NVRAM  administratively down down    
ATM0/0/0                   unassigned      YES NVRAM  down                  down    
Router(config-if)#int fa0/0
Router(config-if)#mtu 1501 
% Interface FastEthernet0/0 does not support user settable mtu.
Router(config-if)#int fa0/1
Router(config-if)#mtu 1501
% Interface FastEthernet0/1 does not support user settable mtu.
Router(config-if)#do sh ver | incl IOS
Cisco IOS Software, 1841 Software (C1841-BROADBAND-M), Version 12.4(1a), RELEASE SOFTWARE (fc2)
Router(config-if)#

Outdated IOS but this MTU thingy probably hasn't changed.

Regards,
Peter