Configuring Xconnect on Cisco 3750 L3 Switch

[lmanavalan]

Hi

I have a situation where i am not able configure the xconnect l2tp tunnel on a Cisco 1841 router due to MTU size of 1546 (cannot defragment).

So i am looking to configure the L2TP on the Cisco Layer 3 Switch.

Is this possible to do it on the Layer 3 Switch or if their a way to overcome the big MTU on the cisco router.

regards

Logesh

[Vinit Jain]

Hello Logesh

Are you talking about L2tpv3 or just the L2tp tunneling protocol. L2tp tunneling is supported on 3750 switch where as i think there is no support for l2tpv3 on 3750. ME-3750 do support L2tpv3.

i tried it on 3750 running 150-2.SE9 image and dont see the command supported.

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750/software/release/12-2_25_see/configuration/guide/scg/swtunnel.html

Cisco1800 series router do not support higher MTU settings. 

R4(config)#int fa0/0
R4(config-if)#mtu 2000
% Interface FastEthernet0/0 does not support user settable mtu.
R4(config-if)#ip mtu ?
  <68-1500>  MTU (bytes)

Hope this helps.

Regards

Vinit

[lmanavalan]

Hi

Thanks for your reply.

Unfortunately I cannot use the 802.1q tunnelling because its not purely switch environment.

I have core router I need to pass through.

regards

Logesh 

[Vinit Jain]

Hi Logesh,

I dont think you have much option. The only other option (if you cant use lower MTU) would be to use a different router.

Please let me know if you have any other questions.

Regards

Vinit

PS: Please mark the question as answered if ur query has been resolved. Also, please rate useful posts.

[lmanavalan]

Hi

I tried with the Cisco 1841 but I am not able to alter the MTU size.

It a requirement that I cannot defragment the MTU.

regards

Logesh

[Vinit Jain]

Hello Logesh

As mentioned before, you cannot increase the MTU on 1841 router. For higher MTU support, you will have to use a different router and thus the suggestion to upgrade the router from 1841 to a different one.

Regards

Vinit