Now you have to configure the cluster:
Assign name to each IP number. I suggest names as follows:
MASTER, SLAVE1, SLAVE2, SLAVE3
Go to: Desktop / Preferences/ RaspBerry Pi Configuration:
For easy access to all 4 boards from another computer we use VNCviewer:
From Desktop press: ALT + CTRL + T for entering Terminal mode:
$hostname -i
Write down name given and associated IP number. You need the information for connection remotely.
From your controlling / remote computer we can now access each board individually after downloading VNCviewer.
https://www.realvnc.com/en/connect/download/viewer/
Technical consideration is whether to disable desktop in order to improve performance. My answer is NO. The Desktop only requires approx. 35 Kb running.