From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?UTF-8?B?UMOhZHJhaWcgQnJhZHk=?= <P@draigBrady.com>
Subject: redundant reverse DNS on NFS mount or umount
Date: Tue, 17 Feb 2009 15:22:35 +0000
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I've a problem where reverse DNS is being done by the NFS server.
This is very problematic when the DNS server goes away.
As far as I can see there should be no lookups being performed
because I've nothing in /etc/hosts.{allow,deny} and just
numeric hosts in /etc/exports.

I can simulate this easily by putting a bad nameserver in /etc/resolv.c=
onf
and restarting the nfs server. Any mounts will take then take ages.
Others seem to have had this issue as well, but possibly with
non numeric names in /etc/exports:
http://marc.info/?l=3Dlinux-nfs&m=3D110977757630297&w=3D2
http://marc.info/?l=3Dlinux-nfs&m=3D111015343008456&w=3D2

Here are my config details:

# rpm -q nfs-utils
nfs-utils-1.1.0-6.fc8

# cat /etc/resolv.conf
search company.com
nameserver 192.168.2.110

# cat /etc/exports
/home   192.168.2.25(async,rw,all_squash,anonuid=3D500,anongid=3D500)

Any ideas appreciated.

cheers,
P=C3=A1draig.