HTTP 303 See Other vs 525 SSL Handshake Failed
HTTP 303 (See Other) is a 3xx Redirection response, while 525 (SSL Handshake Failed) is a 5xx Server Error response. 303 indicates that the server is redirecting to a different resource using GET, typically after a POST operation (Post/Redirect/Get pattern). In contrast, 525 means that cloudflare-specific. SSL/TLS handshake with the origin server failed.
Description
The server is redirecting to a different resource using GET, typically after a POST operation (Post/Redirect/Get pattern).
When You See It
After form submissions to prevent resubmission on browser refresh.
How to Fix
Follow the Location header with a GET request. This is intentional — part of the PRG pattern.
Description
Cloudflare-specific. SSL/TLS handshake with the origin server failed.
When You See It
When origin SSL certificate is expired, misconfigured, or incompatible.
How to Fix
Check origin SSL certificate validity. Ensure TLS version compatibility. Renew expired certificates.
Key Differences
303 is a 3xx Redirection response, while 525 is a 5xx Server Error response.
HTTP 303: The server is redirecting to a different resource using GET, typically after a POST operation (Post/Redirect/Get pattern).
HTTP 525: Cloudflare-specific. SSL/TLS handshake with the origin server failed.
You encounter 303 when after form submissions to prevent resubmission on browser refresh.
You encounter 525 when when origin SSL certificate is expired, misconfigured, or incompatible.
When to Use Which
For 303 (See Other): Follow the Location header with a GET request. This is intentional — part of the PRG pattern. For 525 (SSL Handshake Failed): Check origin SSL certificate validity. Ensure TLS version compatibility. Renew expired certificates.