The only complicated part of this is that, due to the fact that our web servers do not have a public IP address assigned to them, you have to SSH to them from either the master VM or the load balancer VM. To do this, you can set up SSH key authentication to the minions from either of these two VMs. If you are reading this book, you will be familiar with how to perform such a task.
When you log in to the web server VMs, perform the following task in both VMs.
Import the gpg key for the Salt repository:
Run the following to create the repository:
dsala@web-00:~$ echo "deb http://repo.saltstack.com/apt/ubuntu/16.04/amd64/latest xenial main" \
| sudo tee /etc/apt/sources.list.d/saltstack.list
Once the repository has been added, run apt update, and you should be able to see the repository listed:
Proceed to install the salt-minion package:
dsala@web-00:~$ sudo apt install salt-minion -y
Enable and check the status of the salt-minion service by running the following:
dsala@web-00:~$ sudo systemctl enable salt-minion --now && systemctl status salt-minion
You should see the same messages we saw in the CentOS LB virtual machine.