If you experience problems going to certain websites, the problem may lie in your domain name server settings rather than an actual site outage. Your device uses the primary DNS server to take the web address you enter and resolve it into a numerical address necessary to make the connection. If that fails, your device tries to use the designated secondary DNS server.
You can locate your DNS settings in your operating system's network settings to troubleshoot problems and share the information with support professionals.
Determining Primary DNS on Mac
To determine your primary DNS on a Mac, access the Network Preferences through the network icon on the toolbar or the Mac's System Preferences pane. Once there, you see a list of wired and wireless connections. Selecting the current connection brings up details and displays an Advanced button.
Clicking Advanced brings up a window with options for viewing and changing settings for the network. Heading to the DNS tab shows a list of DNS servers in order, where the first one is the primary DNS server.
Seeing Primary DNS on Windows
Windows 10 computers also have a network utility that allows you to see your DNS servers alongside other network preferences. To access it, right-click the network icon in the taskbar and select Open Network & Internet Settings. This window has a Change adapter options link that displays all the wired and wireless network connections.
Double-click the network you want to check to bring up its properties. Click Details to find the preferred DNS server settings alongside information such as your IP address, default gateway and physical hardware address.
Checking Mobile Primary DNS Settings
If you need to find your primary DNS server for the Wi-Fi connection used on your iPhone or iPad, start by launching the Settings app. Select the Wi-Fi option to see the network to which you're currently connected. Tapping the information icon on the far right of a network name brings up all the network settings and options. Scroll down to the DNS section and select Configure DNS. Along with options to automatically or manually select DNS servers, this screen lists the DNS servers, beginning with the primary server.
You also go into the Settings app if your phone or tablet runs Android. Select the Wi-Fi option to show the available networks. Press and hold down your current network until you see the option to Modify Network, as this brings up more network settings. Look for an option to show advanced options and select Static where it says IP Settings. You can now scroll down and see your primary and secondary DNS settings.
Troubleshooting DNS Server Issues
Along with not connecting to a particular website successfully, other signs of DNS server issues include pages that connect slowly or need to be reloaded due to errors. If you suspect a DNS issue, check first that the website is online. You can use a website status checker online, ask a friend to visit the site, or try to connect using your phone's cellular connection.
After you verify the issue likely is due to your DNS settings, contact your service provider for help. You can try changing your DNS server options to new addresses. If you do, make sure the DNS servers are legitimate because attackers can set up servers to redirect you to harmful websites.
The process for changing DNS settings varies by device. For example, you can do it right from the DNS server list on a Mac, while Windows 10 users need to access the Properties option through their connection status window, select their IPv4 or IPv6 connection, and then select Properties again to edit DNS server options. Android and iOS mobile users need to set their connection settings to manual to be able to change DNS options.