cd /var/named
perl -pi -e 's/ns1.abc.com/ns3.abc.com/' *.db
service named restart (or however you wish to restart)
# echo "action=rewrite&value=named" >> /usr/local/directadmin/data/task.queue[/quote]
Note that the above will update the serial numbers within one minute, and then restart BIND about a minute later.
Note that the [i]#[/i] is NOT typed; it means you have to do it as root.
Jeff