This error usually pops up when the proxy can’t communicate with the backend server. Check your logs—both proxy and backend—to see if there’s any connection failure.
Also, if you’re using SSL/TLS, make sure your certificates are valid and properly configured. A misconfigured cert can cause this error too.
Also, if you’re using SSL/TLS, make sure your certificates are valid and properly configured. A misconfigured cert can cause this error too.
