SSHD reverese DNS lookup failures after IP change

From: spunchick (cuddihy_at_gmail.com)
Date: 10/19/05 

Date: 19 Oct 2005 13:00:43 -0700

Hi All

I have a bsdi based box with SSHD.

The IP on this box was changed - moved between networks - so the
DNS server is now different that it was before.

The problem I am having is a lag when authentication. I can initiate
the ssh connection, enter my credentials, and then hit a big lag in
time while it attempts to reverse DNS lookup my client IP.

I have edited my resolv.conf file to have the proper IP address. I
have restarted the SSHD, but I am still seeing the following in my
logs:

<38> Oct 18 15:22:23 sshd[835]: Could not reverse map address
10.24.201.247.

And a tcpdump shows that sshd is for whatever reason trying to go to
the old IP address:

9:06:19.930660 10.24.204.94.32223 > 192.168.250.16.53: 45689+ PTR?
247.201.24.10.in-addr.arpa. (44)
19:06:20.127768 10.24.201.247.2094 > 10.24.204.94.22: . ack 2066 win
64048 (DF)
19:06:24.927964 10.24.204.94.32223 > 192.168.250.16.53: 45689+ PTR?
247.201.24.10.in-addr.arpa. (44)
19:06:29.928137 10.24.204.94.32224 > 192.168.250.16.53: 45690+ PTR?
247.201.24.10.in-addr.arpa.prv. (48)
19:06:34.928108 10.24.204.94.32224 > 192.168.250.16.53: 45690+ PTR?
247.201.24.10.in-addr.arpa.prv. (48)

It would seem that ssh is getting that from somewhere. I'd
appreciate any suggestions.

Thanks!

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