CloudFlare Dynamic DNS Client

Bare minimum bash script to use CloudFlare DNS API for Dynamic DNS. To get your domain on CloudFlare DNS for just go to https://cloudflare.com and they will walk you through the process.

Installation

It uses jq for JSON parsing. So you may download it from https://stedolan.github.io/jq/download/ or just copy paste the script in terminal.

Windows

It works on Git Bash!

git clone https://github.com/parthpower/CloudFlare-DDNS-Client.git
cd CloudFlare-DDNS-Client
chmod +x cf_ddns.sh
# Install jq for 64 bit Windows
curl https://github.com/stedolan/jq/releases/download/jq-1.5/jq-win64.exe > jq.exe

Linux

git clone https://github.com/parthpower/CloudFlare-DDNS-Client.git
cd CloudFlare-DDNS-Client
chmod +x cf_ddns.sh
# Install jq for 64 bit Linux
curl https://github.com/stedolan/jq/releases/download/jq-1.5/jq-linux64 > jq
# sudo apt-get install jq
chmod +x jq

macOS

I have no idea but it should work.

How do I run it?

1. Get zone id and API Key from CloudFlare Dashboard.

2. First Run:

   ./cf_ddns.sh --key <api key> --zone <zone id> --email <your email> --interval 60 --config config.ini --save test.example.com test2.example.com | tee log.txt

3. Once you have the config file, just ./cf_ddns.sh

4. Done! You can find all the DNS records on the CloudFlare dashboard.

./cf_ddns.sh -h for help.

Credits

• ipify.org for the simplest API to get IP.
• httpbin.org for the debugging help.
• Tutorial for Arg Parse
• Ton of StackOverflow and https://unix.stackexchange.com help.
• CloudFlare for the awesome API.
• GitHub and NameCheap for the free domain in education pack.

Notes

• To save number of API calls this script updates the A record only when the host IP changes. It does not periodically check if the record is modified by other means. You can use --always-update-dns to update the record entry at the interval.

• What is DNS record? https://www.cloudflare.com/learning/dns/dns-records/ (Psst: We are just messing with A record here)

• Works on CloudFlare API v4

• Maybe use sed instead of jq in future. Pull-Requests are welcomed.

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