414 Error

A 414 URI Too Long error occurs when the URL requested by the client is longer than the server is willing or able to interpret.

While the HTTP standard does not define a strict universal maximum URL length, most webservers and proxies impose safety limits (often between 2,048 and 8,192 characters) to defend against memory exhaustion and buffer overflow attacks.

Determining why

• A web form with huge amounts of data was mistakenly submitted using the GET method instead of the POST method, stuffing hundreds of form fields into the URL query string.
• A website redirect loop kept appending parameters to the end of the URL over and over.
• A client or third-party tracking script generated runaway analytics parameters.

Steps you could possibly take:

• Check the address bar - Inspect the link you clicked. If you see repeated strings or a massive block of text in the address bar, the link is broken.
• If you are the website developer:
  • Switch large forms from method="GET" to method="POST" so data travels in the request body rather than the URL.
  • In nginx, increase the buffer limit if necessary using large_client_header_buffers.
  • In Apache, adjust the LimitRequestLine directive.

Source: RFC 9110 Section 15.5.15 (HTTP Semantics)