Namebench is a great little tool for finding the fastest DNS settings for your area. Your particular ISP may not have the fastest DNS servers so this tool will give you alternatives to use for your area.
Install namebench easily from the terminal in Ubuntu with:
sudo apt-get install namebench
After installing, run namebench in the terminal by typing namebench and press enter. The program will launch and will look similar to the photo above. There are several options you can change, but I went with all of the default settings. My computer is getting old and we only have a 3.0mbps speed at work so the whole process of determining the best DNS server took about 20 minutes. At home I have 20.0mpbs and the process was definitely quicker.
After completion namebench will create an HTML file and launch it in your browser. Below is the recommended settings to use:
Now that you have your recommended DNS settings, you need to physically change them in Ubuntu.
Right click the network connection icon near the top right of your screen and on the menu click "Edit connections..." If you are connected to the internet with a wired connection, you will edit that connection. If connected with a with a wireless connection, you will edit the wireless connection.
Select your connection and click the "edit" button. Click the "IPv4 Settings" tab and for Methods you will select "Automatic (DHCP) addresses only" and then in the "DNS Servers" box, input the three DNS servers recommended to you with each one separated by a comma (but all on the same line). Click save and close your network connections box. Thats it. Ive waited a few minutes for the new DNS servers to work properly or you could simply reboot your computer and they will be active.
You can also check to see what DNS servers you are using by typing this into a terminal:
It will give you some sort of output info that looks like this.
# Generated by NetworkManager
If the instructions above for changing your DNS servers are challenging, I'll be including screenshots of every step in tomorrows article.