Matt Hite <lists@beatmixed.com> wrote:
Hi, Jan. It's a great presentation and I really love your approach. However, I am curious -- why was IP-in-IP not pursued? I know the presentation mentioned the MTU issue, but your final solution seemed full of enough pitfalls itself (ie -- lots of cooperation from numerous groups, people, and processes) that raising MTU in your network might be an easier proposition. Thought you might have went into it a bit in the video, that's all. Any insight?
We have come to the conclusion that Path MTU Discovery on the internet at large... doesn't work so well. :-) With IP-in-IP or GRE, our MTU increases, so either we keep the MTU the same (to the outside) and declare (internally) our own largest packet to be smaller than 1500 or change the MTU (internally) to be larger than 1500 (to account for the overhead). Either way, we end up with an MTU that's different between at least two of the client, the LB and our server. The idea of using the DSCP bit then seemed to be more reasonable to us. -Jan