Broken PMTUD for . + TLD servers, was: Re: Smallest Transit MTU

Suresh Ramasubramanian ops.lists at
Mon Jan 10 13:29:25 UTC 2005

On Mon, 10 Jan 2005 22:42:28 +1100, Mark Andrews <Mark_Andrews at> wrote:
> > I receive DNS responses > 500 bytes every day (reported by PIX firewall). So
> > it is an issue, no matter wgat is recomended in RFC.
>         The correct thing to do is to fix your firewall to handle the
>         EDNS responses.

It is a cisco pix, right?  Maybe just replacing the thing with a 1U
openbsd box will work wonders.

Suresh Ramasubramanian (ops.lists at

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