Re: VerifyReverseMapping=no but sshd still attempting reverse DNS

From: Darren Tucker (dtucker_at_dodgy.net.au)
Date: 05/25/04 

Date: Tue, 25 May 2004 00:37:11 +0000 (UTC)

In article <mb6dnZaNRrjfri_dRVn-tw@giganews.com>,
Jim Garrison <jhg@athensgroup.com> wrote:
>I have VerifyReverseMapping set to 'no', but my sshd is still
>attempting to verify the reverse mapping, based on a packet
>trace with tcpdump. This is causing long delays in logging in
>from remote locations without rDNS entries.
>
>Any way to prevent sshd from even attempting the rDNS lookup?

Depends on what ssh software and version you're using, and what's causing
the lookups.

Assuming you're using an older OpenSSH, you could try adding "-u0"
to sshd's command line. Newer versions have UseDNS which supercedes
VerifyReverseMapping. 

-- 
Darren Tucker (dtucker at zip.com.au)
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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