Putting Your Own DNS Servers in ClearOS


I've been using a CentralPointe server as a gateway server in my home for years. DirectPointe (I'm on the board) used to offer these, but no longer does, so it had gotten out of date and wasn't being supported anymore. Fortunately, the same system (based on Point Clark Networks code) is available from the Clear Foundation as ClearOS.

I like this software because it allows me to manage content filtering, etc. for my family centrally rather than relying on filtering software installed on each machine. It also provides intrusion detection and other services. The whole thing is based on Linux, of course, but there's a handy Web interface that makes it easy to set everything up and configure the box. ClearOS was easy to install. I just downloaded the ISO image, burnt it to DVD, and then booted the DVD and followed the intructions. The installation is straightforward.

One problem I had was I don't like relying on the DNS that my ISP provides. I'd rather use OpenDNS. I couldn't figure out how to do this--even though I knew you could--and it wasn't easy to find in the documentation or using a Google search. I finally found it by clicking around and decided to document how I did it here.

The trick is to turn off "automatic DNS" on the external interface and then the Web tool will show you boxes where you can enter the IP addresses of your DNS hosts. So, the first step is to edit the interface:

That page will have a checkbox for automatic DNS that is on by default. Uncheck it.

Once you've unchecked the "automatic DNS" box and clicked "Confirm" you'll return to the interface configuration page and see that the DNS server is now a set of input boxes rather than static text:

You can see that I entered the IP addresses for OpenDNS. Now, I'm using DNS servers of my choosing rather than the default from my ISP. You might wonder why I care. One reason is performance. Another is reliability. Most of the time when my family has complained that "the Internet is down" what's really been at fault is the ISP's DNS. The last reason is the additional protection against phishing and content I don't want in my home that OpenDNS provides. It's just one last measure of protection.