How to automatically update a Content Filter when an IP address changes

Tech Lockdown Team

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Updated September 5, 2024

If you're trying to configure your home router to use a content filter or parental control service, you might need to account for IP address changes to ensure that filtering continues to work properly.

Most home networks have a dynamic IP address, which is an address that is subject to change (usually when you reset your internet connection). Customizable content filtering services typically require you to specify your home network IP address in order to connect to the filter.

Example of adding a home network IP address to OpenDNS Home

Just like you have a home address that represents where you physically live, an IPv4 address represents the address of your home internet connection. When the filtering service receives network traffic from your internet connection (you visit a webpage), it will check the IPv4 address and match it to the filter settings associated with your network address.

If your IPv4 address changes and the content filtering service is using your old IP address, your filter and potentially your entire internet connection will stop working because the service won't be able to find the matching filter settings. 

When an IPv4 address changes, it's similar to you moving into a different house. If you move to a different house you always change your shipping address on all of the services you use. You need to do the same thing when your IPv4 address changes. 

This tutorial will walk you through setting up a Dynamic DNS (DDNS) service to automatically handle IP address changes. Instead of using an IP address to represent your home network, like 123.45.67.89 , we will configure a hostname like myhomenetwork.ddns.net.

Check Filter Support for Dynamic DNS

Before setting up a dynamic DNS service, verify that the filtering service you use supports using a hostname. 

Services, like the  Tech Lockdown filter , support dynamic hostnames.

However, if you're using a service like  OpenDNS Home , hostnames aren't supported. Instead, you have to use their  IP updater software . 

Using an IP updater VS DDNS

It might seem simpler to set up an application, like the one provided by OpenDNS, to send IP address changes to the filtering service.

The issue with this approach is that the updater client has to be running on a computer that is constantly connected to the home network. If you turn of the computer and your internet connection resets, the IP change won't be sent to the filter. As a result, filtering will stop working.

Additionally, if you install a VPN on the computer that runs the IP updater application, it will send the wrong IP address to the filter service and break filtering for the entire network.

Furthermore, it's easy to circumvent filtering with this approach by uninstalling the IP updater application and restarting the router. This would change the IP address of the home network, but without updating the filter with the new IP.

Using a DDNS service is one of the best methods for handling IP address changes.

Sign up for a Dynamic DNS Service

We'll use a Dynamic DNS service called  NoIP  to automatically handle IPv4 address changes.

Sign up for NoIP , which is a free Dynamic DNS service. 

Make sure that you receive emails from NoIP. Mark them as important and star them. You do not want to miss these expiration emails

Note: With a free account, you will receive an email every 30 days to confirm that your hostname is still active. You must confirm every 30 days or the hostname will stop working. You can pay for the service if you don't want to have to do this every month.

When you receive an expiration email, make sure to always verify your hostname so that it doesn't expire.

Create a Hostname

You'll use NoIP to create a hostname like myhomenetwork.ddns.net to represent your Home Network.

Get started by opening  NoIP.com  in another browser window. I'll create the address techlockdown.ddns.net.

After you login, navigate to `Dynamic DNS` and copy the hostname you created.

Notice that NoIP already knows about your IPv4 address.

Now we need to configure our home network to connect with NoIP so that it knows about any changes to our Home Network Address.

Login to your Router

The router is the device that also handles Wifi. Sometimes the router and modem are combined into one device. In other cases, you might use a modem and router seperately.

Check the back of your internet router for login instructions (if you didn't set this up yourself).

Try either IP Address in your browser's address bar:

192.168.0.1192.168.1.1

Connect router to DDNS service

Find theDynamic DNSsection in your router. This is probably in an Advanced Settings or WAN settings section.

• Centurylink router example:

• Xfinity router example:

In NoIp, navigate toDynamic DNSand copy the hostname you created

Go back to the Dynamic DNS (DDNS) settings in your router.

Most routers allow you to select NoIP as the service provider. If not, you'll manually configure. Choose the option supported by your router:

• If your router has a NoIP dropdown, enter your account login, password, and the hostname you just copied into the corresponding fields:

• If your router does not have a NoIP dropdown, but allows manual configuration, enter your NoIP account email, password, and hostname.
• Enter dynupdate.no-ip.com into the server address field

Test Connection

Test NoIP to make sure that when your IPv4 address changes NoIP detects the change.

• Restart your router. You can restart via the router's admin panel or by simply unplugging it and then plugging it back in.

• Check your public IPv4 address by going to  whatismyip.com
• Go back to the `Dynamic DNS` section of Noip and make sure that the IP address is the same as the IPv4 address on whatismyip. You might need to wait 5-10 minutes.

Update filter to use DDNS hostname

Once you confirm that the DDNS service works properly, you can update your filtering account to use a hostname instead of an IP address.

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