Web Proxies

A web proxy can help your system communicate outside your network securely and with increased performance. For example, you can direct your system’s outbound requests through an enterprise proxy.

You can configure your system to use a proxy one of the following ways:

  • Automatic: You specify only the proxy credentials (if needed). Using DHCP, your system obtains a URL to automatically download a proxy auto-configuration (PAC) file.
  • Semi-automatic: You specify the proxy credentials and URL for automatically downloading a PAC file.
  • Manual: You specify the proxy address, port, and credentials. (This method lets you configure your system with only one proxy.)

If your configuration includes automatically downloading a PAC file, there must be an expiration associated with the file so the system knows when to download a new one. Make sure your PAC file server includes an Expires header in its HTTP response (for example, Expires: Wed, 30 Oct 2016 09:30:00 GMT).

Your system can authenticate with a proxy using the following methods:

  • Digest authentication (with either MD-5 or SHA-256 digest)
  • NTLM authentication (only NTLMv2 is supported)
  • Basic authentication (this insecure method is disabled by default)
  • No authentication (or null authentication, meaning the proxy server doesn’t require credentials)

Your system supports the following services when configured to use a web proxy:

  • Directory servers
  • Provisioning service
  • Software updates

Enable the System to Use a Web Proxy

By default, your system configuration doesn’t use web proxies.

Procedure

  1. In the system web interface, go to Network > Primary Network > Web Proxy Settings.
  2. Select Enable Web Proxy.

Set Up Automatic Web Proxy Configuration

With automatic web proxy configuration, your system obtains a URL for downloading a proxy auto-configuration (PAC) file through DHCP option 252.

Procedure

  1. In the system web interface, go to Network > Primary Network > Web Proxy Settings.
  2. Select Automatic Configuration.
  3. Select Enable WPAD.
    This option enables the web proxy auto-discovery protocol (WPAD), which helps your system automatically download the PAC file on your network using DHCP option 252.
  4. Enter the Proxy User Name and Proxy Password.
  5. Select Save.
Your system automatically downloads and reads the PAC file specifying the proxy rules. The system also automatically downloads subsequent files before the current file expires.

Set Up Semi-Automatic Web Proxy Configuration

With semiautomatic web proxy configuration, you must specify the URL your system uses to download a proxy auto-configuration (PAC) file.

Procedure

  1. In the system web interface, go to Network > Primary Network > Web Proxy Settings.
  2. Select Automatic Configuration.
  3. If checked, clear the Enable WPAD check box.
  4. Enter the Proxy User Name and Proxy Password.
  5. Enter the PAC URL from which your system downloads the PAC file.
  6. Select Save.
Your system automatically downloads and reads the PAC file specifying the proxy rules. The system also automatically downloads subsequent files before the current file expires.

Manually Update the PAC File on the System

Even if you set up your system for automatic or semi-automatic web proxy configuration, you can still manually download a new PAC file from the server.

The PAC file may update on the server much sooner than its expiration date. In this situation, you don’t have to wait for the system to automatically download the latest version.

Procedure

  1. In the system web interface, go to Network > Primary Network > Web Proxy Settings.
  2. Select Update PAC File to fetch the latest version of the file from the server.

Manually Configure a Web Proxy

You can manually configure your system to communicate with a web proxy by providing a proxy address, port, and credentials (if required).

This method lets you configure your system with only one proxy.

Procedure

  1. In the system web interface, go to Network > Primary Network > Web Proxy Settings.
  2. If checked, clear the Automatic Configuration check box.
  3. Enter the Proxy Address and Proxy Port.
  4. Enter the Proxy User Name and Proxy Password.
  5. Select Save.