Error: "400 Bad Request - Request Header or Cookie Too Large" using browser routed through Cloud SWG

Products

• Cloud Secure Web Gateway - Cloud SWG

Issue/Introduction

Page doesn't load when using a browser routed through the WSS platform.

A message: "400 Bad Request - Request Header or Cookie Too Large" may appear.

Cause

This is happening because some websites do not accept the proxy headers added by WSS (X-Bluecoat-Via and X-Forwarded-For).

Resolution

If you are a UPE customer you can remove the XFF and Via header in policy.

If you are a portal customer you will need to raise a support case to have the XFF removed for the destination server in policy.

Alternatively you can create a TLS/SSL exemption for the site, but this may not be ideal as this removes any Content and Malware scanning capabilities for the site.