How to change the DNS settings on a Cisco EPC3940AD router

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Setup Router Staff
(Last Updated: ) | Reading Time: 4 minutes

This page shows how to change the DNS settings on the Cisco EPC3940AD router.

Other Cisco EPC3940AD Guides

This is the dns guide for the Cisco EPC3940AD.We also have the following guides for the same router:

What is the DNS setting on a Router

When you connect a router to the Internet it gets a few settings from your ISP automatically. One of the settings that the ISP sets in your router is the DNS setting. DNS stands for Domain Name System and it is used to convert Internet names into actual IP addresses. For instance, when you go to "", your are really connecting to an IP address that is mapped through DNS to a number such as:

This mapping happens automatically every time you visit any page on the Internet.

Why Change Your Router's DNS Setting

Some ISPs choose to abuse the DNS system and map unknown names to servers that they control. This can be done in a way that you don't know it is happening since your router is getting its DNS settings from your ISP. For instance, if you have one of these ISPs who is hijacking your DNS, and you try to surf the web to "" and "" does not exist, you might get a page back from your ISP with local advertisements on it.

By changing your DNS setting in your router you will effectively change the DNS setting for every computer on your network. This is because when a device is connected to your network your router automatically hands out its own DNS settings to that device. This way you can protect your entire network from ISP hijacking with just one setting.

What Should I Change My DNS To

There are 2 really great DNS servers on the Internet that you can choose from right now: Google Public DNS and OpenDNS. If you are not sure which one to pick then just use Google Public DNS.

When you change the DNS settings in your router, you usually have to enter a Primary and a Secondary setting. The secondary is only used if the primary can not be located. Here are common settings:

If you want to use Google Public DNS, use the following settings:

If you want to use OpenDNS, use the following settings:

Login To The Cisco EPC3940AD

To get started configuring the Cisco EPC3940AD DNS page you need to login to your router. If you are already logged in you can skip this step.

To login to the Cisco EPC3940AD, follow our Cisco EPC3940AD Login Guide.

Change the DNS settings on a Cisco EPC3940AD

If you followed our login guide above then you should see this screen.

router setup
This is the setup page from your Cisco router.

Now that you have finished logging into the Cisco EPC3940AD router you should see the Home page.

To change your DNS settings you need to click the option of Setup at the top of the page. Then under that click Lan Setup.

Configure the DNS section of your Cisco EPC3940AD

router IP address lan home network
This is the lan page from your Cisco router.

You should now see a page similar to the one seen here. Scroll down until you see the LAN 1 Static DNS 1 boxes. Enter the primary DNS address you want to use in the four boxes available.

Below that in the four boxes labeled LAN1 Static DNS 2 enter the secondary DNS address. This address is only used if the first can't be used for some reason.

There is no need to enter a third DNS address but if you want to go ahead and enter a third DNS address in the four boxes labeled LAN1 Static DNS 3. There is a good chance that this address will never be used.

When you are finished click the button labeled Save Settings at the bottom of the page.

Possible Problems when Changing your DNS settings

Most devices on your network will not begin using the new DNS settings until they have been rebooted. After rebooting a device you can go to it's network settings and verify that it is using the DNS servers that you specified.

Other Cisco EPC3940AD Info

Don't forget about our other Cisco EPC3940AD info that you might be interested in.

This is the dns guide for the Cisco EPC3940AD.We also have the following guides for the same router: