From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Andrew E. Mileski" <andrewm@isoar.ca>
Subject: NAT and DNS/NTP servers
Date: Fri, 30 Apr 2004 22:52:14 -0400
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I'm observing lost packets when a gateway doing NAT also locally hosts
a server for DNS or NTP.  I believe this the result of the ambiguous
conditions that can exist when routing server-to-server packets coming
into the gateway.

I can avoid it by specifying --to-source ports in a SNAT rule for NTP,
or with DNAT and --to-destination port to force usage of the gateway's
server (which is likely the best solution).  I've not tried this on DNS
yet, but I expect it will solve the problem as well.

Is this a known situation for these protocols (and similar)?  Or am I
barking up the wrong tree?

Thanks.

-- 
Andrew E. Mileski