Set up a VirtualBox VM

Having a virtual machine (VM) locally is extremely useful to test provisioning your remote host. This can be really useful when you plan to host your application on an external provider like DigitalOcean. Together with ansible it will help you learn how to automate your deployment.

Setup VirtualBox

Download a Ubuntu iso image and use it to set up a VM.
Install VirtualBox.
- Create a virtual machine. It is important to select “Bridged Adapter” in the Network options. This will allow your host to communicate with the VM via TCP/IP. Configure other options (memory, disk size, etc.) as desired.
- Optionally, I would suggest to install the Guest Additions. This allows you to resize the screen to the window size. First, select from the menu “Insert Guest Additions CD”, then after mounting it you need to execute autorun.sh. After reboot you can activate from the menu “View > Autoresize Guest Display”
- Optionally, I would also activate the bidirectional Drag and Drop from the menu.
Next, you need to add your user to the sudoers group, which is not done by default on installation. For this, you need to follow these instructions:
```
su -
sudo adduser <username> sudo
```
The root password is the same password as the one you selected for your user in the installation step.
Next, you need to allow the VM user to execute sudo without being prompted for a password. This will allow the execution of the ansible tasks that require superuser privilges, without being prompted for a password. For this, on your VM, create a new file /etc/sudoers.d/<username> inside the /etc/sudoers.d directory with following content:
```
<username> ALL=(ALL) NOPASSWD:ALL
```
This is not really safe, and you could be more specific with the permissions (e.g. ALL = NOPASSWD: /bin/apt, /bin/apt-get …), but we don’t want to mess around with security at this point.
Next, you want to install an ssh server on your machine, so you can access it from your client via ssh. For this, execute the following commands:
```
sudo apt-get install openssh-server
sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.bck
egrep -v "^$|^#" /etc/ssh/sshd_config | sudo tee /etc/ssh/sshd_config
echo "Port 22" | sudo tee -a /etc/ssh/sshd_config
sudo systemctl enable ssh --now
```
Explanation:
- The first line installs the ssh server
- The second one copies the default configuration of the ssh server to a separate file as a backup and for later reference
- The third line only extracts the lines in the original file that are not blank lines or comments, so we can only see the configured variables at one glance
- The fourth line opens port 22 for ssh connections. For security reasons you could change this to any other port between 1024 and 65536, so attackers have a harder time to guess the correct port
- The last line finally starts the ssh server and enables it to launch on startup
Next, you need to generate an ssh key on your host, and copy it to the VM with
```
ssh-copy-id -i ~/.ssh/id_ed25519.pub <username>@<VM IP Address> -p 22
```

Setup Ansible

First things first, you need to install Ansible on your local machine. I would recommend to install globally, using pip, but the one provided by your local pyenv installation. You could also install it with your package manager, but it might not be the latest version and would be harder to upgrade.

Let’s take a look at following two files: our inventory development and our playbook playbook.yml:

The inventory specifies a hostname that is addressed in the playbook as hosts: vbox. This tells Ansible which hosts to run this playbook on. There are three other parameters specified for the host:

ansible_host: this is the IP address of the node that ansible will ssh to to execute the playbook
ansible_port: this is the port for the ssh connection
ansible_become: this instructs ansible to become a specific user on the remote host during playbook execution. By default this is root. Since most of the commands require superuser privileges, I would rather specify it here than for each task repeatedly, and only in case I need less privileges to perform an action, I specify it per task level.

The playbook goes through the installation process of pyenv step by step

It uptates the apt packages list (for debian/ubuntu obviously)
It installs the packages required by pyenv for building
It installs pyenv via an install script
It updates the .profile of the user to initialize pyenv correctly.

There is a required environment variable ``, that can be specified with the flag -e on playbook execution, which controls for which user pyenv should be installed. Here is how you would execute the playbook:

ansible-playbook -i development -e user=victor playbook.yml

This command will install pyenv for the specified user on the VM and you can check it by logging in as the user on the VM and typing pyenv into the terminal, which should output all pyenv actions available.

Setup VirtualBox

Setup Ansible

Further reading: