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Date: Tue, 8 Jul 2003 13:13:39 +0200
From: Socketd <db@traceroute.dk>
To: Terry Lambert <tlambert2@mindspring.com>, hackers@freebsd.org
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Subject: Re: 5 "Advanced" networking questions
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On Tue, 08 Jul 2003 03:17:00 -0700
Terry Lambert <tlambert2@mindspring.com> wrote:

> Socketd wrote:
> > Ok, anyway to prevent sending ICMP's when ttl = 0? Or do I need a
> > firewall?
> 
> I guess you want to do this so that you can break path MTU
> discovery and fail to properly exchange packets with the DF
> bit set in the headers, and which don't take into account
> intermediate links with smaller MTUs, like VPNs or PPPOE
> links?
> 
> What exactly are you getting from disabling ICMP, besides a
> broken network connection to some systems you may wish to be
> able to exchange packets with?

I don't want to disable ICMP, just don't want to respond when ttl=0,
meaning when my firewall/gateway is on a "traceroute path".

br
socketd