nginx + cookies + firefox = 400 Bad Request

[Maxim Dounin]

Hello!

On Sun, Dec 14, 2008 at 01:26:59PM +0100, Oliver Pestring wrote:

> Hi guys, this week is was about to move partially to nginx for all
> static content. The full switch was planned in about a month on a new
> server. I followed this guide
> http://www.dikant.de/2008/07/10/nginx-as-a-reverse-proxy-for-apache/ and
> it worked instantly. After some minutes I got some t-calls about saying
> that the page isnt reachable with a 400 - Bad Request for them. It runs
> a vbulletin-forum and a Mantis-Bugtracker, it happens on both.
> 
> Some hours later I could nail that problem down to nginx (same with 0.5x
> from etch and 0.632 from lenny) and firefox users (versions 2&3). It
> works again if the related domain-cookies are deleted. apache2 doesnt
> cause any trouble, same for IE/Opera-users.
> 
> Tried a quick google search and I found endless posts on a lot of sites
> with the same 400 problem and ff after they switched to nginx (even
> famous ones like electronicarts). Sadly none if these contain a solution
> besides cleaning the cookies but that doesnt seem to help for long
> according to that posts.
> 
> As I have over 60% FF-users Im a little afraid of the results and
> switched back to pure apache for the moment. Is there any known solution
> to this problem on serverside? May a selfcompiled-0.7-version help on
> this? Couldnt find anything related in the changelog.

You should tune large_client_header_buffers in your nginx config, see 
http://wiki.codemongers.com/NginxHttpCoreModule#large_client_header_buffers 
for details.

The problem AFAIK is vbulletin which sets enormous number of 
various cookies.

Maxim Dounin