Add a proxy to a particular host only in mac

Question

I want to apply proxy settings to a particular host only (e.g., www.apple.com) in Mac OS X. How can I do it?

In System Preferences there are only options for bypassing proxy settings for particular hosts.

Answer 1

You can use the following proxy.pac file to send all traffic to apple.com through the proxy 1.2.3.4 while still going directly to all other hosts:

function FindProxyForURL(url, host) {
    PROXY = "PROXY 1.2.3.4"

    // Apple.com via proxy
    if (shExpMatch(host,"*.apple.com")) {
        return PROXY;
    }
    // Everything else directly!
    return "DIRECT";
}

1. Save this script as proxy.pac(or any other name you like) on a web server. This can be a local web server (http://localhost/proxy.pac). This is required as of OSX Lion.
2. Go to the System Preferences.
3. Select Network.
4. Select the network you want to change (i.e. "WiFi").
5. Click Advanced... button.
6. Click Proxies tab
7. Check [x] Automatic Proxy-Configuration.
8. In the URL: field, type in the URL to the file you've created in step 1., for example: http://localhost/proxy.pac. (note: local paths will not work in modern OSX)
9. Click Save and Apply

Voila! Your own proxy-configuration

For more information on the format of the proxy.pac file have a look at http://en.wikipedia.org/wiki/Proxy_Auto-Config as starting point.

Answer 2

Actually you can use the file:///path/to/file scheme for the URL, instead of having to rely on a web server.

For example:

file:///Users/youruser/var/proxy/proxy.pac

Answer 3

Adding to @heiglandreas's answer...

@jnbek's solution did not work on Mac OSX for me and I was looking for a simple solution.

So, I created a new folder and copied the pac file into that. Then, I started a simple web server on OSX on port 80 from that folder itself.

Just go into the folder & run this command. Please change the port from 80 to something else if its already occupied.

python -m SimpleHTTPServer 80

Now, I could easily get the proxy.pac file from http://localhost/proxy.pac. Or, for different port use: http://localhost:PORT/proxy.pac.

Answer 4

@Rehmat's answer is great, but it's not updated for python 3 and Mac OS X Big Sur:

1. Create a proxy.pac file in a new directory called proxy-web (in whatever parent directory you want):

   function FindProxyForURL(url, host) {
       PROXY = "PROXY 1.2.3.4"
   
       // Apple.com via proxy
       if (shExpMatch(host,"*.apple.com")) {
           return PROXY;
       }
       // Everything else directly!
       return "DIRECT";
   }
   

2. Start a web server in that directory where your proxy.pac file is located

   cd proxy-web
   ls
   # proxy.pac
   python -m http.server 80
   

3. Open Apple -> System Preferences

4. Click Network

5. Select the specific network in question (ex: "Thunderbolt Ethernet" or "Wi-Fi")

6. Click Advanced

7. Select the Proxies tab

8. Check the Automatic Proxy Configuration box, input URL: http://localhost/proxy.pac

9. Click OK and Apply but do not close network settings

10. Test that it's working by going to apple in CHROME (not SAFARI -- for me, our corporate URLs and proxy did not seem to work in Safari but Chrome worked just fine): apple.com

11. Test in Safari. If it's not working click "Renew DHCP Lease" under the Advanced → TCP/IP tab back in network settings

12. Run further tests in your favorite browser by going to non-apple URIs (ex: google.com). If you're proxying a specific subdomain, you'll also want to test other subdomains that are not supposed to be proxied.