[103160] in North American Network Operators' Group
Re: mtu mis-match
daemon@ATHENA.MIT.EDU (Michael Holstein)
Thu Mar 20 11:32:50 2008
Date: Thu, 20 Mar 2008 11:30:00 -0400
From: Michael Holstein <michael.holstein@csuohio.edu>
To: ann kok <annkok2001@yahoo.com>
CC: nanog@merit.edu
In-Reply-To: <868830.11903.qm@web53307.mail.re2.yahoo.com>
Errors-To: owner-nanog@merit.edu
> but I still don't know why mtu can cause this problem
>
Blocking ICMP (specifically type 3,code 4) can also cause this ..
because it breaks path MTU discovery (pmtud).
The first part of this doc helps explain the issue :
http://www.cisco.com/warp/public/105/pmtud_ipfrag.html
Cheers,
Michael Holstein
Cleveland State University
