Creating an ssh key file and passing it to the hosts

Mode details instructions

ssh-keygen
ssh-copy-id ubuntu-1
ssh-copy-id ubuntu-2

From now on ssh to the servers will be done without asking for password. Make sure you have python (aka Python 2) installed on all the servers:

sudo apt-get update
sudo apt-get install --no-install-recommends --assume-yes python-apt

Alternatively add the following to the inventory file to use Python 3 on the remote servers.

[virtualhosts:vars]
ansible_python_interpreter=/usr/bin/python3

Let's try running the Ansible command again:

yonit@ansible_server:/etc/ansible$ ansible virtualhosts -m ping

ubuntu-2 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}
ubuntu-1 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}