PMTUD broken with

Fernando Gont fernando at
Fri Feb 4 04:31:29 CET 2011

On 02/02/2011 07:09 p.m., Jared Mauch wrote:

> Blocking icmp can be silly, but blocking icmpv6 is problematic....

Since msots v4 stacks rely on PMTUD, and since many stacks do not
implement blackhole detection, filtering ICMP is as silly as filtering

Surprising that lots of v6 docs claim "as opposed with v4, you cannot
filter ICMPv6" -- you shouldn't have filtered icmpv4 frag needed, either!

Fernando Gont
e-mail: fernando at || fgont at
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1

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