nanog mailing list archives

Re: MTU to CDN's


From: joel jaeggli <joelja () bogus com>
Date: Mon, 8 Jan 2018 15:08:51 -0800

On 1/8/18 2:55 PM, Dovid Bender wrote:

Hi,

N00b here trying to understand why certain CDN's such as Cloudfare have
issues where my MTU is low. For instance if I am using pptp and the MTU is
at 1300 it wont work. If I increase to 1478 it may or may not work.
PMTUD has a lot of trouble working reliability when the destination of
the PTBĀ  is a stateless load-balancer.

If your tunnel or host clamps the mssĀ  to the appropriate value it can
support. it is highly likely that connection attempts to the same
destination will work fine.
TIA.




Current thread: