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From: "Andrew E. Mileski" <andrewm@isoar.ca>
To: netfilter@lists.netfilter.org
Subject: NAT and DNS/NTP servers
Date: Fri, 30 Apr 2004 22:52:14 -0400	[thread overview]
Message-ID: <409310DE.2020004@isoar.ca> (raw)

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



             reply	other threads:[~2004-05-01  2:52 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-05-01  2:52 Andrew E. Mileski [this message]
2004-05-01  7:19 ` NAT and DNS/NTP servers Antony Stone
2004-05-01 17:42   ` Andrew E. Mileski
2004-05-01 17:49     ` Andrew E. Mileski
2004-05-01 18:05     ` Antony Stone
2004-05-01 19:51       ` Andrew E. Mileski
2004-05-01 20:00         ` Andrew E. Mileski
2004-05-01 20:21         ` Antony Stone
2004-05-01 20:48           ` Andrew E. Mileski
2004-05-01 21:07             ` Antony Stone
2004-05-01 21:42               ` Andrew E. Mileski
2004-05-01 23:17                 ` Antony Stone
  -- strict thread matches above, loose matches on Subject: below --
2004-05-02 13:49 Steve Jones
2004-05-03  0:14 ` Andrew E. Mileski

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