ah opps the worker to worker case wouldn
ah opps the worker to worker case wouldn't be a 521 anyway.
so your worker is fetching another subdomain? If the other subdomain is unproxied, it's worth noting the worker fetch request goes through the full cdn pipeline as if it was proxied. A Common issue is your SSL/TLS Mode (under SSL/TLS -> Overview) is Flexible, so the Worker's trying to connect to your origin over http/80 and your origin only supports https/443, need full or full (strict). Otherwise 521 is a generic connection refused (could be firewall/etc). I assume it works fine not through the worker
so your worker is fetching another subdomain? If the other subdomain is unproxied, it's worth noting the worker fetch request goes through the full cdn pipeline as if it was proxied. A Common issue is your SSL/TLS Mode (under SSL/TLS -> Overview) is Flexible, so the Worker's trying to connect to your origin over http/80 and your origin only supports https/443, need full or full (strict). Otherwise 521 is a generic connection refused (could be firewall/etc). I assume it works fine not through the worker
