Service Instances and bridge domains MTU

Folks,

I just want to start off by saying thanks to all of the regulars in the group for the consistent knowledge sharing.

I am a long time Lurker, but I have stumbled onto something which has me puzzled to say the least.

I am attempting to create a bridge domain between two interfaces on an ASR 1006 and am running into a strange MTU issue.

Everything is working fine I am tunneling my q-in-q/802.1q traffic popping and pushing the necessary tags and what not, however when I try to ping accross it using a 1500 byte packet with the df bit set i cannot. I can ping across it with a 1400 byte packet but of course this is not the magic number.

I have tried setting the MTU at the interfaces involved (gig interfaces) but cannot for the life of me figure out why this is happening. This happens with a single tag as well as a stack of them. I do not have a BDI interface at the moment, but I am not sure i really need one since I am transiting the box. The only thing that i am able to think of at the momment is some sort of system wide MTU setting. This may become a no duh moment for me in the end, but I cannot find the command if it exists. Any guidance would be appreciated. If there is any information that is lacking let me know and i will get it out here.

Thanks to all,
Eric

Blogs and organic groups at http://www.ccie.net
Received on Sat May 11 2013 - 04:01:42 ART