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431

Request Header Fields Too Large

The server is unwilling to process the request because its header fields are too large.

Common Causes

  • Too many cookies
  • Large Authorization header
  • Excessive custom headers

Fix Solutions

Reduce header size

Clear unnecessary cookies or reduce header content.

Increase server limit

Configure server to accept larger headers if necessary.

Code Examples

# Increase header buffer size
large_client_header_buffers 4 32k;

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