Open Network Preferences through: Applications > System Preferences > Network

Disabling IPv6 on macOS

To disable IPv6 on your machine with the following commands in Terminal (Accessible through /Applications/Terminal.app)

To Get List of Hardware

networksetup -listallnetworkservices

This is to double check the interface names recognized by the operating system matches those in Network Preferences.

To Disable IPv6 on Desired Interface

sudo networksetup -setv6off "Interface_Name"

Note: Change "Interface_Name" to the name of the desired interface you wish to disable. (NOT case sensitive)

Enable IPv6 on your machine with the following commands in Terminal (Accessible through /Applications/Terminal.app)

sudo networksetup -setv6automatic "Interface_Name"

Note: Change "Interface_Name" to the name of the desired interface you wish to enable. (NOT case sensitive)

This has been tested to work on v10.12 and v10.13