Hetzner DDNS update script

hetzenr-ddns-update.md

Auto check latest VPS IP and update DDNS record on Hetzner

Last updated on: 2022/06/26

cd /root/

wget https://gist.githubusercontent.com/ookangzheng/c1f6894470d362c4356911691c24f67d/raw/update-hetzner-dns.sh

chmod +x update-hetzner-dns.sh

nano /etc/crontab

*/1 * * * *  root /root/update-hetzner-dns.sh

service crontab restart

update-hetzner-dns.sh

#!/usr/bin/env bash

# -------------------------------------------------------
# A shell script that auto update VPS IP to Hetzner DNS
# Written by: @ookangzheng
# Last updated on: 2022/06/26
# Licensed under the Apache License, Version 2.0 (the "License") http://www.apache.org/licenses/LICENSE-2.0;
# -------------------------------------------------------

# Debug 
# set -ex

API_TOKEN="<TOKEN>"
IP=""
TTL="10"
TYPE="A"
NAME="<SUBDOMAIN>"
ZONE_NAME="<ROOT DOMAIN>"
ZONE_ID="<ZONE_ID>"

## ZoneID: https://dns.hetzner.com/
## API_TOKEN: https://dns.hetzner.com/settings/api-token

parent_path="$(dirname "${BASH_SOURCE[0]}")"
FILE=${parent_path}/update-hetzner-dns.log
if ! [ -x "$FILE" ]; then
  touch "$FILE"
fi

LOG_FILE=${parent_path}'/update-hetzner-dns.log'

### Write last run of STDOUT & STDERR as log file and prints to screen
exec > >(tee $LOG_FILE) 2>&1
echo "==> $(date "+%Y-%m-%d %H:%M:%S")"

# http://whatismyip.akamai.com
# https://ipinfo.tw/ip

IP=$(curl -s -X GET http://whatismyip.akamai.com --max-time 3)

if [ -z "$IP" ]; then
    echo "Error! Can't get external ip from http://whatismyip.akamai.com"
    exit 0
  fi
echo "==> External IP is: $IP"

## GET Zone ID
ZONE_ID=$(curl "https://dns.hetzner.com/api/v1/zones" -H "Auth-API-Token: $API_TOKEN" \
 | jq -r ".zones[] | select(.name == \"${ZONE_NAME}\") | .id ")

## GET Domain ID
RECORD_ID=$(curl "https://dns.hetzner.com/api/v1/records?zone_id=$ZONE_ID" -H "Auth-API-Token: $API_TOKEN" \
 | jq -r ".records[] | select(.name == \"${NAME}\") | .id  ")

## Update Record
hetzner_update=$(curl -X "PUT" "https://dns.hetzner.com/api/v1/records/$RECORD_ID" \
     -H "Content-Type: application/json" \
     -H "Auth-API-Token: $API_TOKEN" \
     -d $"{
  	\"value\": \"$IP\",
  	\"ttl\": $TTL,
  	\"type\": \"$TYPE\",
  	\"name\": \"$NAME\",
  	\"zone_id\": \"$ZONE_ID\"}")