How to Point Chrome & Edge to a Specific IP for a Website

You can configure Google Chrome and Microsoft Edge to resolve a specific website to a custom IP address using the --host-resolver-rules flag. This is useful for testing or development, such as:

• Testing a new website deployment: Access the new version in Chrome and the live version in Firefox.
• Side-by-side comparison: Open different versions of the same website and easily copy and paste between them.

Note: This technique uses an advanced, unsupported feature. Our web design team uses this hack every day, and we encourage you to give it a try. However, it is not covered by Ecenica Support, and please use it at your own risk.

Steps for Google Chrome on Mac

1. Quit Chrome
   Close all running instances of Google Chrome.

2. Open Terminal
   Open Terminal by pressing Cmd + Space, typing Terminal, and pressing Enter.

3. Run Chrome, or Edge with Custom Host Resolver Rules

   Enter the following command:

   open -a "Google Chrome" --args --host-resolver-rules="MAP example.com 100.100.100.100"

   Or for Edge:

   open -a "Microsoft Edge" --args --host-resolver-rules="MAP ecenica.com 100.100.100.100"

   Be sure to replace 100.100.100.100 with the IP address of your Ecenica server.

4. Test the Configuration
   Visit example.com in Chrome. It will now resolve to the specified IP address.

5. Restore Default Settings
   Quit Chrome and reopen it normally to reset DNS resolution.

Steps for Windows

1. Quit Chrome
   Close all running instances of Google Chrome.

2. Locate Chrome’s Shortcut

   • Right-click the Google Chrome shortcut on your desktop or Start menu.
   • Select Properties.
3. Edit the Target Field
   In the Target field, append the following:

   –host-resolver-rules=’MAP example.com 100.100.100.100′

   Example:

   ‘C:\Program Files\Google\Chrome\Application\chrome.exe’ –host-resolver-rules=’MAP example.com 100.100.100.100′

4. Save and Launch Chrome
   Click OK to save. Use this shortcut to launch Chrome and resolve example.com to the specified IP.

5. Restore Default Settings
   Close all Chrome windows and reopen Chrome normally.

Limitations and Notes

• Not Always Reliable: Support for --host-resolver-rules varies across Chrome versions and operating systems. It may not always work as intended, particularly with IPv6.
• Temporary Effect: This only affects Chrome during the current session.
• Advanced Users Only: Requires command-line or shortcut modifications.

For long-term changes, consider using your system’s hosts file or a local DNS server. Since this feature is experimental, it is not covered by Ecenica Support.

Browser Compatibility

Google Chrome

• Supports --host-resolver-rules: Yes
• Usage: Allows mapping specific domains to custom IP addresses on a per-session basis.

Firefox

• Supports --host-resolver-rules: No
• Alternative: Use extensions like SwitchHosts or configure a proxy server to map DNS.

Safari

• Supports --host-resolver-rules: No
• Alternative: Use system-wide changes (e.g., modify /etc/hosts) or configure a custom proxy.

Microsoft Edge

• Supports --host-resolver-rules: Yes
• Usage: Same feature as Chrome due to Edge’s Chromium base.