nsupdate

#!/bin/sh
if which nsupdate >/dev/null; then

ETH=br-lan
DOMAIN=router.nnxx
DNS=176.9.204.50
SUB=$(cat /proc/sys/kernel/hostname)
ECHO=$(which echo)
NSUPDATE=$(which nsupdate)
IP=$(ip addr show dev $ETH | grep 'inet ' | awk '{split($2,a,"/");print a[1];}')

$ECHO "server $DNS" > /tmp/nsupdate
$ECHO "debug yes" >> /tmp/nsupdate
$ECHO "zone $DOMAIN." >> /tmp/nsupdate
$ECHO "update delete $SUB.$DOMAIN" >> /tmp/nsupdate
$ECHO "update add $SUB.$DOMAIN 60 A $IP" >> /tmp/nsupdate
$ECHO "send" >> /tmp/nsupdate

$NSUPDATE -v /tmp/nsupdate 2>&1

else
    echo installo nsupdate, riavvia lo script dopo
    sleep 5
    opkg update
    opkg install bind-client
fi