Qlik Sense HTTP Header size restriction

SAML authentication fails with the following error:

HTTP Error 400. The size of the request headers is too long.

The entire return code looks as such:

 
 
 

Bad Request - Request Too Long

 

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HTTP Error 400. The size of the request headers is too long.

 
 

 

Environment:

Qlik Sense Enterprise on Windows  any version

 

Resolution:

Windows and Qlik Sense have a limitation on HTTP Header sizes.

The maximum header length is 16 KB.

Steps to be applied on the Qlik Sense Server:

1. Open the Windows Registry Editor with Administrative Permissions.
2. Create (or locate and change) the following keys and configure them with the desired value: 
   
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters\MaxFieldLength (64 - 65534 (64k - 2) bytes)
   
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters\MaxRequestBytes (256 - 16777216 (16MB) bytes)
    
3. Restart the Server
4. Open the Qlik Sense Management Console
5. Open the Proxy used and navigate to the Settings of the Proxy
6. In the Advanced section, input the desired Max header size (bytes)

 

The HTTP header length can be up to 64kb.

We recommend that you investigate the impact on other programs on the machine, as changing these settings is a system-wide change.

 

For more information, see Add Session on Qlik Sense for developers.