networksetup

"networksetup -- configuration tool for network settings in System Preferences." - man networksetup

networksetup is a standard tool on MacOS

Examples

List all network services

Network Services are not the same as hardware devices.

$ networksetup -listallnetworkservices
An asterisk (*) denotes that a network service is disabled.
Ethernet Adapter (en4)
Wi-Fi
Thunderbolt Bridge
$ networksetup -listnetworkserviceorder
An asterisk (*) denotes that a network service is disabled.
(1) Ethernet Adapter (en4)
(Hardware Port: Thunderbolt Ethernet Slot 0, Device: en4)

(2) Wi-Fi
(Hardware Port: Wi-Fi, Device: en0)

(3) Thunderbolt Bridge
(Hardware Port: Thunderbolt Bridge, Device: bridge0)

Modify DNS for a device

Using Empty is pretty unintuitive. This is used in a few other places in networksetup.

$ networksetup -getdnsservers Wi-Fi
There aren't any DNS Servers set on Wi-Fi.
$ networksetup -setdnsservers Wi-Fi 8.8.8.8
$ networksetup -getdnsservers Wi-Fi
8.8.8.8
$ networksetup -setdnsservers Wi-Fi Empty
$ networksetup -getdnsservers Wi-Fi
There aren't any DNS Servers set on Wi-Fi.

Show info for the device named Wi-Fi

networksetup -getinfo "Wi-Fi"

Show all connected hardware ports

networksetup -listallhardwareports

Show all search domains

networksetup -listallnetworkservices |
  tail -n +2 |
  xargs -I :: networksetup -getsearchdomains "::"

Create a bunch of VLAN interfaces

for X in {1..32} ; do
  sudo networksetup -createVLAN "vlan${X}" en3 "${X}" ;
done ;

Delete a bunch of VLAN interfaces

for X in {1..32} ; do
  sudo networksetup -deleteVLAN "vlan${X}" en3 "${X}" ;
done ;