Fast command line option

If you want to force the apt-get to use IPv4 or IPv6 only one time, follow these steps. This feature is available after the 0.9.7.9~exp1 version of apt-get.

First, make sure your version of 

apt-get is newer than 0.9.7.9~exp1 by running the following command:

apt-get --version

The result will be something like this:

apt 1.0.1ubuntu2 for amd64 compiled on Oct 28 2014 20:55:14

If the version checks out, then you can force IPv4 with:

apt-get -o Acquire::ForceIPv4=true update

or IPv6:

apt-get -o Acquire::ForceIPv6=true update

This will update the repositories resolving the URLs in sources.list to IPv4 only.

Persistent option

To make the setting persistent, create the file 99force-ipv4 in /etc/apt/apt.conf.d/.

sudoedit /etc/apt/apt.conf.d/99force-ipv4

Put the following contents in it:

Acquire::ForceIPv4 "true";

Save the file, and you’re good to go. If you want to force IPv6 instead, change the 4 to 6 in the file name and settings. To choose between one of them, test with the fast method and see which works better.

Source: Vultr Docs