There are a couple of conditions that can cause this issue. One is a redirect URL prefix pointing to a suffix of itself. If you're doing any redirection, check for this.

The other rare, but still more common, instance occurs when generating a get request which has too many characters for a geniune URL (typically 2048 to 4096 bytes). This means switching back to a post from a get. I see that you state that you are using a post method, so I would examine the raw HTTP headers to verify that your client isn't erroneously sending the request via the get method. Stranger things have been known to happen.

Also, I don't know how to find this in Apache, but if you could find out the max length of requests and how to set this, it may help. CGI.pm can also throw an error if you exceed maximum post length, but I believe that it's just a simple die message and doesn't generate a 414. Probably generates a 5xx status code on the die.

Cheers,
Ovid

In reply to (Ovid) Re: 414 Request-URI Too Large by Ovid
in thread 414 Request-URI Too Large by damian

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