request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

What This Error Means

Docker failed to reach the registry due to a network/timeout error.

How to Fix It

1. Retry with debug logs: docker --debug pull <image>.
2. Validate DNS and connectivity to the registry host from the same machine.
3. If you use a proxy, ensure Docker is configured to use it (daemon + CLI env).
4. If the registry is internal, confirm health and TLS cert validity.

Why It Happens

• DNS, firewall, proxy, or VPN is blocking registry traffic.
• The registry is temporarily unavailable or overloaded.
• Corporate proxies are interfering with TLS or long-lived connections.

How to Verify

1. Re-run the original pull/push and confirm it completes.
2. Confirm CI runners can reach the same registry endpoint.

Common CLI Output

request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

Prevention Tips

• Use a proxy/cache registry to reduce dependence on upstream availability.
• Keep runner network configuration consistent (DNS/proxy/firewall).