How to Setup a Proxy Server in Linux?

To set up a proxy server on Linux, you can follow these steps, categorized into automatic configuration, manual configuration, and dedicated proxy server setup.

Automatic Proxy Configuration

If you are provided with a script address, or you want Linux to automatically discover settings instead, you can configure in the system settings or environment variables.

Using Desktop GUI

• Open System Settings (this might be "Settings" in Ubuntu).
• Select Network > Proxy to the Proxy configuration section.
• Change the Proxy setting to Automatic.
• Paste in the script address provided by the network administrator.
• Save the Setting & Apply.

Using Environment Variables

• Open a Terminal Window and edit the /etc/environment file.
• In the file, create the proxy variables, entering the proxy for http_proxy, https_proxy, and no_proxy.
• Log off the session and back on or restart the system for changes to take effect.

Manual Proxy Configuration

This type of configuration will allow you to configure a proxy for overall system use or for individual applications.

System-Wide Proxy

• Edit the file and place the proxy variables in both upper-case and lower-case. This will match all environments to ensure proper functionality to the applications you are using.
• Include exceptions for local traffic using no_proxy.
• Once you save the changes, restart or logout/login for the variables to reflect.

Single User Proxy

• Modify proxy settings in the specific file located in the user's home directory.
• Add export commands for proxy variables like http_proxy and https_proxy.
• To reload the shell configuration, either log out and back in, or run source ~/.bashrc.