A virtual URL is used to redirect a user to another URL when the user needs to be challenged for credentials.
Each realm can have its own virtual URL. In addition, you can also set the virtual URL based on the individual realm sequence.
The default virtual URL is www.cfauth.com. Blue Coat recommends changing the default virtual URL to a hostname that is resolvable to the IP address of the ProxySG.
A virtual URL can be specified in the Management Console > Configuration tab > Authentication and choosing the realm to which you want to assign the virtual URL.
In the command line interface (CLI), a virtual URL can be specified using the virtual-url command. For example, to set a virtual URL for a NTLM realm "testntlm" you would use the following:
SGOS#(config)security ntlm edit-realm testntlm
SGOS#(config ntlm testntlm)virtual-url proxysg-virtualurl.example.com