Skip to main content.

There are several reasons why some pages on SLAC's web servers may be restricted or unreachable:

  1. The page is in a directory marked SLACONLY on our production UNIX web server ( This requires the page be accessed from a computer whose IP number begins with 134.79.
  2. The page is on a web server that is blocked at the SLAC firewall.
  3. The page is on a Windows web server and requires a Windows username and password that have been issued by SLAC.
  4. The page is on UNIX web server in a directory protected by the ".htaccess/.htpasswd" mechanism set up by the owner of the directory.

For case #1 and #2, anyone who has a computer on the SLAC local area network ("inside the firewall") will be able to see the pages with no additional action required.

For case #3 you will be prompted for a username and password. You need to supply your SLAC Windows username and password (sometimes as "slac\username"). If you don't currently have one you may apply for one.

For case #4 you will need to contact the owner of the directory that you wish to access and request that they authorize you for access.

If you are outside of the SLAC firewall, there are still ways to access pages that are restricted by case #1 and #2.

One mechanism that works for all users is to connect via a Citrix connection to SLAC's Windows Terminal Server farm. To do this, you will need a SLAC Windows account, Independent Computing Architecture (ICA) account (necessary to access the farm) and the free client software on your computer. Once you connect to the farm you will have a Windows session that allows you to start a web browser and view internal SLAC pages.

Windows users have another alternative, to use a Virtual Private Network (VPN) connection, also known as a Point To Point Tunneling Protocol (PPTP) connection. You must have a SLAC Windows Account. Follow the instructions at to set up the connection.

UNIX and Linux users can also use SSH to connect. For this method you will need a SLAC UNIX account and must have a machine that has SSH installed. Then, from a command shell type:

ssh -L 4080:www:80

Then when you type http://localhost:4080/path/ in your browser you are actually connecting to

Last update: