IPv4-IPv6 DNS server configuration on Linux

Configuring DNS servers for proper resolution on Debian Linux.

Configuration

Simply visit the below directory with your choice of text editor:

/etc/resolv.conf

You'll likely already have something from within the file, and it's likely Google's DNS service. Regardless, for IPv6 compliance, it should now look something like this:

nameserver 8.8.8.8
nameserver 8.8.4.4
nameserver 2001:4860:4860::8888
nameserver 2001:4860:4860::8844

Save the file.

Check for proper resolution via IPv4:

ping -c 3 google.com

You should get something like this:

PING google.com (172.217.10.142) 56(84) bytes of data.
64 bytes from lga34s16-in-f14.1e100.net (172.217.10.142): icmp_seq=1 ttl=55 time=1.97 ms
64 bytes from lga34s16-in-f14.1e100.net (172.217.10.142): icmp_seq=2 ttl=55 time=2.58 ms
64 bytes from lga34s16-in-f14.1e100.net (172.217.10.142): icmp_seq=3 ttl=55 time=2.59 ms

--- google.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 1.972/2.382/2.592/0.289 ms

For IPv6:

ping6 -c 3 google.com

Should get much the same result as above.

If it hangs, then it might be a misconfiguration of your network, IPv6 is likely not routing correctly (if using IPv6 DNS), or port 53 may be filtered or blocked completely.