script for use with `nsupdate` to update linux client DNS on a DNS server... in this instance, I am targeting a Windows Server DNS server 2003/2008/2012+. I have manually created the PTR and A records once, and granted the Everyone ACE the "Write" permission in the DACL of the PTR and A records.

nsclient_update.sh

#!/bin/sh
#original from http://community.spiceworks.com/topic/262635-linux-does-not-register-on-the-windows-ad-dns
# reply of Phil6196 Oct 1, 2012 at 12:41 AM (EDT)
ADDR=`/sbin/ifconfig eth0 | grep 'inet addr' | awk '{print $2}' | sed -e s/.*://`
HOST=`hostname`
echo "update delete $HOST A" > /var/nsupdate.txt
echo "update add $HOST 86400 A $ADDR" >> /var/nsupdate.txt
echo "update delete $HOST PTR" > /var/nsupdate.txt
echo "update add $HOST 86400 PTR $ADDR" >> /var/nsupdate.txt
nsupdate /var/nsupdate.txt