#!/bin/bash set -eu . /etc/ddns-update/ddns-update.conf DDHOST="https://www.ddnss.de/upd.php" if ! DNSRESULT="$(host $DDNSNAME)" ; then echo "Could not resolve IP address for '$DDNSNAME', no update." exit 0 fi DNSIP4="$(echo "$DNSRESULT" | grep -m 1 -oE '[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}$' || true )" DNSIP6="$(echo "$DNSRESULT" | grep -m 1 -oE '[0-9a-f]{1,4}:.+:[0-9a-f]{1,4}' || true )" REALIP4="$(wget -q -O - https://ip4.ddnss.de/meineip.php | \ grep -m 1 -oE '[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}' || true )" REALIP6="$(wget -q -O - https://ip6.ddnss.de/meineip.php | \ grep -m 1 -oE '[0-9a-f]{1,4}:.+:[0-9a-f]{1,4}' || true )" if [ -z "$REALIP4" -a -z "$REALIP6" ] ; then echo "Could not detect real IP addresses, exiting." exit 0 fi echo "Current DNS: IPv4=$DNSIP4, IPv6=$DNSIP6." echo "Detected: IPv4=$REALIP4, IPv6=$REALIP6." if [ "$REALIP4" == "$DNSIP4" -a "$REALIP6" == "$DNSIP6" ] ; then echo "IP address unchanged, no update." else echo "IP address changed: $DNSIP4 → ${REALIP4}, $DNSIP6 → ${REALIP6}, updating ddns." wget -q -O - $DDHOST'?key='$KEYAUTH'&host='$DDNSNAME'&ip='$REALIP4'&ip6='$REALIP6 \ | grep -oE "Updated .+ hostname." || echo "Update not confirmed, it might have failed." fi