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I've got a problem with FirePHP. FirePHP doesn't work anymore on my Server (Debian 6 Squeeze with Apache2).

When I am loading my site in my Firefox with FirePHP enabled, I receive an 502 error and an error message from my hoster Hetzner, which says 'request or response is too long'.

Wenn I am loading the same site with Firebug enabled an FirePHP disabled, the site works perfect.

The problem seems that the header, which FirePHP creates is too big. Due to my research this problem is more come with nginx servers.

Nevertheless I tried to increase the header size of my apache with the following config:

LimitRequestFieldSize 32760
LimitRequestLine 32760
LimitRequestFields 32760

But without success! Of course, I restarted the apache and the varnish too, I cleaned the cache. Nothing helped.

At first I thought this might by cause by a programming mistake of myself in our site on the development stage. But the testing stage, which is running on the same server and on the same apache doesn't work, too. However the same site is working fine on my local server installation.

So it seems to be an server problem. That's interesting cause I didn't changed the config and the error accrued the first time on Monday morning. On Sunday FirePHP worked fine.

Seriously I running out of ideas! If anyone has an idea, I will be very thankful.

Thx in advance!


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By default Varnish has a sess_workspace size of 64K, and your entire HTTP header must fit in this. I'd suggest increasing that if your headers are very large.

share|improve this answer
Yeah!You've made my day! I've just added -p sess_workspace=262144 as a startup parameter for varnish and now I works! Thx a lot! – Michi Qne Aug 7 '12 at 16:17

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