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To: Gregory Kuhn <freebsd-net@lists.ctch.net>
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Date: Fri, 20 Aug 2004 10:30:09 -0700
From: Eli Dart <dart@nersc.gov>
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cc: freebsd-net@freebsd.org
Subject: Re: Traceroute Anomaly 
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In reply to Gregory Kuhn <freebsd-net@lists.ctch.net> :

> Hello,
> 
> 
>          I have discovered an anomaly (I am sure it was discovered long 
> ago) when trying to traceroute to my FBSD 4.8 and 4.9 servers.  Here are 
> the details.

Have you set sysctl net.inet.udp.blackhole=1 ?

If so, the FreeBSD box will drop the traceroute UDP probes and you'll 
never see the host itself in traceroute output.

		--eli




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