#Serverless

Cloudflare Worker Cron Watchdog: SPOF Fix and Automatic DNS Failover for the Vercel Proxy Architecture

The third-party CNAME node pool in the optimized proxy setup is a hidden single point of failure (SPOF). This guide implements a zero-cost watchdog using Cloudflare Worker Cron Triggers: Google DoH serves as an external probe to monitor upstream health, with automatic DNS failover and recovery between the optimized CNAME and CF official IPs.