HTTP 426 Upgrade Required vs 522 Connection Timed Out
HTTP 426 (Upgrade Required) is a 4xx Client Error response, while 522 (Connection Timed Out) is a 5xx Server Error response. 426 indicates that the server refuses to perform the request using the current protocol but might after the client upgrades to a different protocol. In contrast, 522 means that cloudflare-specific. TCP connection to the origin server timed out.
Description
The server refuses to perform the request using the current protocol but might after the client upgrades to a different protocol.
When You See It
When a server requires HTTPS or a newer protocol version.
How to Fix
Switch to the protocol specified in the Upgrade response header.
Description
Cloudflare-specific. TCP connection to the origin server timed out.
When You See It
When the origin server is overloaded or network issues prevent connection.
How to Fix
Check origin server health. Verify firewall rules. Check for network congestion.
Key Differences
426 is a 4xx Client Error response, while 522 is a 5xx Server Error response.
HTTP 426: The server refuses to perform the request using the current protocol but might after the client upgrades to a different protocol.
HTTP 522: Cloudflare-specific. TCP connection to the origin server timed out.
You encounter 426 when when a server requires HTTPS or a newer protocol version.
You encounter 522 when when the origin server is overloaded or network issues prevent connection.
When to Use Which
For 426 (Upgrade Required): Switch to the protocol specified in the Upgrade response header. For 522 (Connection Timed Out): Check origin server health. Verify firewall rules. Check for network congestion.