HTTP

HTTP 103 Early Hints vs 522 Connection Timed Out

HTTP 103 (Early Hints) is a 1xx Informational response, while 522 (Connection Timed Out) is a 5xx Server Error response. 103 indicates that used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response. In contrast, 522 means that cloudflare-specific. TCP connection to the origin server timed out.

Description

Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.

When You See It

When a server wants the browser to start loading CSS/JS before the full response is ready.

How to Fix

No fix needed. This optimization helps speed up page loading.

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

1.

103 is a 1xx Informational response, while 522 is a 5xx Server Error response.

2.

HTTP 103: Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.

3.

HTTP 522: Cloudflare-specific. TCP connection to the origin server timed out.

4.

You encounter 103 when when a server wants the browser to start loading CSS/JS before the full response is ready.

5.

You encounter 522 when when the origin server is overloaded or network issues prevent connection.

When to Use Which

For 103 (Early Hints): No fix needed. This optimization helps speed up page loading. For 522 (Connection Timed Out): Check origin server health. Verify firewall rules. Check for network congestion.

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