How to Change Your Mac's DNS Settings

Configuring your Mac's Domain Name Server (DNS) settings is a straightforward process. Even so, there are a few nuances to be aware of to help you get the most out of your DNS server.

You configure your Mac's DNS settings using the Network system preferences pane, where you can use the same instructions for any network connection type.

What You Need

• One or more DNS IP (Internet Protocol) addresses. IP addresses are usually assigned by your Internet Service Provider (ISP), although you are usually under no constraints to use the assigned name servers. Some individuals prefer to use publicly available DNS services, such as Open DNS or Google DNS, on the theory that publicly available DNS servers may be faster than those supplied by a local ISP. If you're not sure which DNS service to use, try Google's namebench application to test the speed of any DNS system.
• Administrative access to your Mac. You need an administrator password to make changes to the network settings on your Mac. If your user account is the only user account on your Mac, then it is also the administrator account.

Opening Your Mac's DNS Settings

1. Launch System Preferences by selecting System Preferences in the Apple menu or by clicking the System Preferences icon in the Dock.

2. Click Network in the System Preferences window to open the Network preferences screen, which displays all the network connection types currently available to your Mac.

3. Select the connection type whose DNS settings you want to change in the left pane and click the Advanced button.

   Only one connection type is usually active—typically Wi-Fi—as indicated by the green dot next to its name. However, the process is basically the same for any connection type you may use: Ethernet, Wi-Fi, Thunderbolt Bridge, Bluetooth, or something else entirely.

4. Click the DNS tab to display two panes. One of the panes contains the DNS Servers, and the other contains Search Domains. This is the screen where you can add or delete DNS entries.

   The DNS Servers list may be empty, it may have one or more entries that are grayed out, or it may have entries in a normal dark text. Grayed-out text implies the IP addresses for the DNS servers were assigned by another device on your network, usually your network router. You can override the assignments by editing the DNS server list on your Mac. When you override DNS entries here using your Mac's Network preference pane, changes only affect your Mac and not any other device on your network.

   Entries in dark text indicate the DNS addresses that were entered locally on your Mac. An empty entry signifies that no DNS servers have yet been assigned.

Editing DNS Entries

If the DNS list is empty or has one or more grayed-out entries, you can add one or more new DNS addresses to the list. Any entries that you add replace the grayed-out entries. If you want to keep one or more of the grayed-out DNS addresses, write down the addresses and then manually reenter them as part of the process of adding new DNS addresses.

If you already have one or more DNS servers listed in dark text, any new entries you add appear below them in the list and do not replace existing DNS servers. If you want to replace one or more existing DNS servers, you can either enter the new DNS addresses and then drag the entries around to rearrange them or delete the entries first and then add the DNS addresses back in the order you want them to appear.

The order of the DNS servers is important. When your Mac needs to resolve a URL, it queries the first DNS entry on the list. If there is no response, your Mac asks the second entry on the list for the necessary information. This process continues until a DNS server returns an answer or your Mac runs through all the listed DNS servers without receiving a response.

Adding a DNS Entry

When you are on the DNS settings screen, you can add a new DNS entry easily.

1. Click the + (plus sign) in the bottom left corner of the screen.

2. Enter the DNS server address in the DNS Servers pane in either IPv6 or IPv4 dot-decimal format—groups of numbers separated by decimal points. An example is 208.67.222.222, which is one of the DNS servers available from Open DNS. Do not enter more than one DNS address per line.

3. To add more DNS addresses, repeat the process.

Deleting a DNS Entry

When you are on the DNS settings screen, you can also delete DNS entries.

1. Highlight the DNS address you want to remove.

2. Click the - (minus sign) in the bottom left corner of the screen.

3. Repeat for each additional DNS address you want to remove.

You can't delete DNS addresses configured by another device (a grayed-out entry).

Using Search Domains

The Search Domains pane in the DNS settings is used for autocompleting hostnames used in Safari and other network services. As an example, if your home network is configured with the domain name example.com and you want to access a network printer named ColorLaser, you normally enter ColorLaser.example.com in Safari to access its status page. 

If you added example.com to the Search Domain pane, then Safari can append example.com to any single hostname entered. With the Search Domain pane filled in, you could enter ColorLaser in Safari's URL field, and it would connect to ColorLaser.example.com.

Search Domains are added, removed, and organized using the same method as DNS entries.

Finishing Up

When you finish making edits, click the OK button. This action closes the Advanced Network sheet and returns you to the main Network Preference pane.

Click the Apply button to complete the DNS editing process.

Your new DNS settings are ready to be used. Remember, the settings you changed only affect your Mac. If you need to alter DNS settings for all the devices on your network, make the changes at your network router.

Test your new DNS provider to make sure everything is set up correctly.