Getting error "HTTP Error 400. The size of the request headers is too long" when trying to access reports with Kerberos authentication enabled

Created
October 08, 2021 23:17

Date Posted: 2019-12-12
Product: TIBCO Spotfire®

Problem:

Solution:

Kerberos Authentication is enabled. Users are able to login to Spotfire, but are not able to open reports. Error is thrown:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd">
<HTML><HEAD><TITLE>Bad Request</TITLE>
<META HTTP-EQUIV="Content-Type" Content="text/html; charset=us-ascii"></HEAD>
<BODY><h2>Bad Request - Request Too Long</h2>
<hr><p>HTTP Error 400. The size of the request headers is too long.</p>
</BODY></HTML>

The most common reason for the error, "HTTP Error 400. The size of the request headers is too long", is the use of Kerberos SSO authentication combined with membership in many active directory groups. The group memberships makes the authentication string grow and depending on the settings on the servers, this may end up with this error.

For a windows server, the settings MaxFieldLength and MaxRequestBytes can block connections if the request becomes too large (the auth header is part of every request). These settings can be edited for the Nodemanager machine to resolve the issue. Please read the referenced Microsoft Knowledge Base Article for more information.

Please be aware that changes to the registry is always needed to be configured carefully. And only make the required changes. It is also a good idea to take a backup of the registry before editing these values.

The following Microsoft Knowledge Base Article describes how to configure "MaxFieldLength" and "MaxRequestBytes" to higher values.
https://support.microsoft.com/en-us/kb/820129