Some strange situation, we are running to webserver Linux/Apache 2.2.22.
Development System runs fine with SAML Authentication QA System throws "Your browser sent a request that this server could not understand. The number of request header fields exceeds this server's limit."
If compared the httpd.conf, the only difference is that the QA System (wich throws the rror) has the following apache setting:
LimitRequestFieldSize 16380
But after checking the Docs, Apaches default Limit is something around 8000 Bytes, so it cant be the source of all evil or?
So we figured it out.
SAML was sending about 90 Headers, our Form altough 20 so we reached the Limit of Apache. That was not the case on our DEV System (different SAML configs).