Use IP over Thunderbolt to connect Mac computers
Connect two Thunderbolt-equipped Mac computers using a Thunderbolt cable, then use Internet Protocol (IP) to communicate between the computers.
Connect a Thunderbolt cable to the Thunderbolt ports on the computers you want to connect.
On your Mac, choose Apple menu
Select Thunderbolt Bridge in the list on the left.
Click Advanced, click DNS, then enter the DNS and search domain addresses if your network requires them. Check with the network administrator or your ISP if you’re not sure what the addresses are.
Click OK, then click Apply.
When you connect computers using IP over Thunderbolt, by default, the computers receive IP addresses using DHCP. To enter an IP address manually or select another way to receive an IP address, use the Configure IPv4 pop-up menu.