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Accessing Internal Webpages from Outside CERN

Using a Proxy with Firefox

This configuration only redirects the web traffic for cern webpages, it does not redirect any other website access.

Create a proxy file using the Terminal app (make sure you don't yet have a file named "generic.pac" in your "Documents" folder!):

cat >~/Documents/generic.pac<<EOF
function FindProxyForURL(url, host) {
if (shExpMatch(url,"**")) {
return "SOCKS5";

// All other requests go directly to the 'Net':
return "DIRECT";

If you have cernbox on your Mac you might want to put the file into ~/cernbox/Documents, so you immediately have it on all devices on which you have cernbox installed.

In Firefox:

  • open the Settings (was Preferences on older macOS/Firefox versions)
  • scroll down to the "Network Settings" section, click on "Settings..."
  • enable "Automatic proxy configuration URL"
  • enter file:///Users/YourLocalMacAccount/Documents/generic.pac

Now when you want to connect to an internal CERN webpage you open an ssh tunnel:

ssh -D 8080

and the open the webpage in question.

You need to disable the Firefox proxy settings when you bring the device on site.