A Zsh script to monitor a site with two origin servers and rotate DNS when the primary one goes down. It requires a settings.zsh file with the following contents:
TOKEN="{{ Cloudflare Token }}"
ZONE_ID="{{ Cloudflare Zone ID }}"
DNS_ID="{{ Cloudflare DNS ID }}"
DOMAIN_MAIN="domain.tld"
SERVER_A="a.domain.tld"
SERVER_B="b.domain.tld"Where the first three are for the Cloudflare API (corresponding to $DOMAIN_MAIN) and the last three are domains. The first domain, $DOMAIN_MAIN is the client facing domain. The other two, $SERVER_A and $SERVER_B should point to your main and backup server respectively. When server A goes down, the script sets the CNAME record for the main domain to $SERVER_B. When server A is back up, the script sets the CNAME record for the main domain back to $SERVER_A.
Only $DOMAIN_MAIN needs to be managed at Cloudflare. The other two hosts do not need to be on Cloudflare. They also do not need to be subdomains of the main domain.
This package requires zsh, curl, and jq to be installed.