Linux Update Dynamic DNS with Cloudflare through Cron

Download Bash script from https://github.com/khaudennis/Scripts/blob/master/Bash/update-cloudflare.sh using wget or curl:

wget -O https://github.com/khaudennis/Scripts/blob/master/Bash/update-cloudflare.sh

curl -O https://github.com/khaudennis/Scripts/blob/master/Bash/update-cloudflare.sh

This script was forked from https://gist.github.com/Tras2/cba88201b17d765ec065ccbedfb16d9a.

Edit the script and modify the zone, dnsrecords, cloudflare_auth_email, and cloudflare_auth_key. The zone is your domain apex aka dennisdoes.net. The dnsrecords is your subdomains aka www.dennisdoes.net or test.dennisdoes.net. Cloudflare_auth_email and cloudflare_auth_key is your Cloudflare account and API Tokens which can be found in "My Profile" on Cloudflare.

Move the script to where you would normally store all your scripts. I placed mine in /usr/local/bin.

Make the script executable:

chmod +x update-cloudflare.sh

Install jq;

sudo apt update && sudo apt upgrade -y && sudo apt install jq -y

Edit crontab to add your script, be sure to change username to the account that owns the script:

sudo crontab -u username -e

Add your script to crontab, pointing it to where you saved the script:

*/1  *  *  *  * username -f /usr/local/bin/update-cloudflare.sh

This script is set to run every minute with the following schedule expression */1 * * * *.

Additional Commands

To view your crontab without modifying it:

sudo crontab -u username -l

Troubleshooting

To check logs for troubleshooting, run the following:

sudo grep -i cloudflare /var/log/syslog

sudo grep "update-cloudflare.sh" /var/log/cron

For Internal Use: \Machine Notes\2022 NIX Crontab