HTTP 202 Accepted vs 521 Web Server Is Down
HTTP 202 (Accepted) is a 2xx Success response, while 521 (Web Server Is Down) is a 5xx Server Error response. 202 indicates that the request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon. In contrast, 521 means that cloudflare-specific. The origin server refused the connection.
描述
The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon.
何时出现
For async operations like batch jobs, email sending, or background tasks that take time to complete.
如何修复
Poll the provided status URL or wait for a callback/webhook.
描述
Cloudflare-specific. The origin server refused the connection.
何时出现
When Cloudflare can't establish a TCP connection to the origin server.
如何修复
Check that the origin server is running and the firewall allows Cloudflare IPs.
主要区别
202 is a 2xx Success response, while 521 is a 5xx Server Error response.
HTTP 202: The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon.
HTTP 521: Cloudflare-specific. The origin server refused the connection.
You encounter 202 when for async operations like batch jobs, email sending, or background tasks that take time to complete.
You encounter 521 when when Cloudflare can't establish a TCP connection to the origin server.
何时使用哪个
For 202 (Accepted): Poll the provided status URL or wait for a callback/webhook. For 521 (Web Server Is Down): Check that the origin server is running and the firewall allows Cloudflare IPs.