Testing your new Google Public DNS settings

Open a command prompt, and run the following command:

On Windows:

tracert -d 8.8.8.8

On Mac OS X:

/usr/sbin/traceroute -n -w 2 -q 2 -m 30 8.8.8.8

On Linux:

sudo traceroute -n -w 2 -q 2 -m 30 8.8.8.8

If the last line of the output does not list 8.8.8.8 as the final hop, or if there are significant timeouts, there may be a network problem preventing you from contacting our servers. Please include the output of the command in any communication with the Google Public DNS team.

If the last line of the output does list 8.8.8.8 as the final hop, continue to step 2.

IPv6

Open a command prompt, and run the following command:

On Windows:

tracert -d 2001:4860:4860::8888

On Mac OS X:

/usr/sbin/traceroute -n -w 2 -q 2 -m 30 2001:4860:4860::8888

On Linux:

sudo traceroute -n -w 2 -q 2 -m 30 2001:4860:4860::8888

If the last line of the output does not list 2001:4860:4860::8888 as the final hop, or if there are significant timeouts, there may be a network problem preventing you from contacting our servers. Try configuring Google Public DNS for IPv4 to diagnose whether the problem is due to IPv6 connectivity on your network. If IPv4 works for you, you may want to revert your IPv6 configuration and use Google Public DNS with IPv4 exclusively. Otherwise, please include the output of the command in any communication with the Google Public DNS team.

If the last line of the output does list 2001:4860:4860::8888 as the final hop, continue to step 2.

Step 2: Verify that Google Public DNS can resolve the selected hostname

IPv4

At the command prompt, run the following command, where hostname is the name that you were having difficulty resolving:

On Windows:

nslookup -debug hostname 8.8.8.8

On Mac and Linux:

dig @8.8.8.8 hostname

If the output shows an answer section with an A record for the hostname, then Google Public DNS is able to resolve the name. Check your settings to make sure your system is correctly configured to use Google Public DNS. If you are still unable to solve the problem, please include the output of the command in any communication with the Google Public DNS team.

If the output does not show an answer for the hostname, continue to step 3.

IPv6

Windows

At the command prompt, run the following command, where hostname is the name that you were having difficulty resolving*.

nslookup -debug -type=AAAA hostname 2001:4860:4860::8888

If the output shows an answer section with an AAAA record for the hostname, then Google Public DNS is able to resolve the name. Check your settings to make sure your system is correctly configured to use Google Public DNS. If you are still unable to solve the problem, please include the output of the command in any communication with the Google Public DNS team.

If the output shows an answer section with an A (IPv4) record for the hostname, then Google Public DNS is able to resolve the name, but the host and/or its nameserver are not configured to return IPv6 results. If you want to verify that you are correctly receiving AAAA records, you can use the hostname ipv6.google.com as a generic test.

If the output for ipv6.google.com, or another host for which you are certain IPv6 records exist, does not show an answer, continue to step 3.

On Mac and Linux

At the command prompt, run the following command, where hostname is the name that you were having difficulty resolving*.

dig @2001:4860:4860::8888 hostname AAAA

If the output shows an answer section with an AAAA record for the hostname, then Google Public DNS is able to resolve the name. Check your settings to make sure your system is correctly configured to use Google Public DNS. If you are still unable to solve the problem, please include the output of the command in any communication with the Google Public DNS team.

If the output does not show an AAAA record for the hostname, this may be because the the host and/or its nameserver are not configured to return IPv6 results. If you want to verify that you are correctly receiving AAAA records, you can use the hostname ipv6.google.com as a generic test.

If the output for ipv6.google.com, or another host for which you are certain IPv6 records exist, does not show an answer, continue to step 3.

*Note: Google properties will not return AAAA records for all users. Please see the Google over IPv6 page for more information about whether your system qualifies.

Step 3: Verify that another open resolver can resolve the selected hostname

At the command prompt, run any one of the following commands, where hostname is the name that you were having difficulty resolving:

nslookup hostname 4.2.2.1

nslookup hostname 4.2.2.2

nslookup hostname 208.67.222.222

nslookup hostname 208.67.220.220

(The first two commands test Level 3's DNS servers. The last two commands test OpenDNS' DNS servers.)

If you are not able to get a successful result, this means that there is most likely a problem with the server you are trying to contact. Wait some time and try running the tests again. This may be a temporary problem on the server's side that will likely resolve itself eventually. If it does not, you should contact the owner of the server.

If you do get a successful result, there may be a problem with Google Public DNS. Please include the output of this command and the one from step 2 in any communication with the Google Public DNS team.