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.
Mô tả
The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon.
Khi bạn thấy mã này
For async operations like batch jobs, email sending, or background tasks that take time to complete.
Cách khắc phục
Poll the provided status URL or wait for a callback/webhook.
Mô tả
Cloudflare-specific. The origin server refused the connection.
Khi bạn thấy mã này
When Cloudflare can't establish a TCP connection to the origin server.
Cách khắc phục
Check that the origin server is running and the firewall allows Cloudflare IPs.
Sự khác biệt chính
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.
Khi nào dùng cái nào
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.