3Com Webcache 3000 (3C16116) manual Bypass the Webcache for plain host names, http//intranet

Proxy Auto Configuration (PAC) File Scripts 51

You can only use a PAC file to configure the Web browsers on client machines when the Webcache is operating in Proxy mode.

You can use the Browser Auto-Configuration screen to create a PAC file which is stored on the Webcache. You can configure the PAC file to:

■Bypass the Webcache for plain host names

■Use a backup Webcache if the first one fails

■Directly access the Web if neither the first or second Webcache is available

Alternatively, you can disable the PAC file that the Webcache creates and use a different PAC file which is located elsewhere on your network.

CAUTION: If you are using Browser Auto-Configuration Files to configure your client machine Web browser settings, and you are using Web Client Blocking to control access to the Internet, you should ensure that Go Direct if no Webcache Available is not ticked in the Browser Auto-Configuration screen. If this box is ticked, the Web browser will bypass the Webcache entirely after reading the Browser Auto-Configuration file, and will never be blocked.

To use the Webcache as a PAC file server, first configure the Webcache PAC file using the Browser Autoconfiguration screen:

1Log in to the Web interface.

2Click Device View on the Toolbar.

3Select System ->Caching ->Browser Auto-Config in the Navigation Tree.

4Tick Bypass Plain Host Names if you want to configure Web browsers to bypass the Webcache for plain host names. These are typically domain

names which do not contain dots, commonly used for Intranet sites e.g.

http://intranet

5Tick Use Backup Cache on Cache Failure if you want to configure Web browsers to use an alternative Webcache in your network if the first one fails. Enter the IP address of the alternative Webcache in the Backup Cache IP Address field. Enter the port number on which the Webcache will be listening for network traffic in the Port field. The default port number is 8080.