Introduction to Vagrant
Vagrant is a tool used to create environments from pre-configured machine images.
Let us say you need an Ubuntu 16.04 server for your project and you want apache web server installed on it, you have two options here
The first one is to get an ISO to install Ubuntu 16.04 server and use virtualbox to boot from the ISO and install the system on a virtual machine, setup SSH server in the VM and setup networking for the VM too.
This method has many drawbacks, how can you share your environment with other developers? If you make any changes to the server how will these changes be sent to all other developers? If you wanted to work on another project which also needs Ubuntu 16.04 server how will you create the new VM? Again from scratch or Clone the previous one?
There is one answer to all the previous questions, that is MANUALLY, you need to send the VM to other developers manually, any changes you make to the servers need to be shared and applied manually, if you wanted to create another VM you need to do it manually.
Of course you are thinking that Vagrant is the other option, yes it is and it automates all other actions mentioned previously.
Vagrant is not only tied to development environments and virtual box, it can be used to create production environments on cloud providers such as AWS, and these environments will be identical to the ones created locally on virtualbox, BUT it is mostly used only for development environments.
installing and using vagrant
To download Vagrant on Ubuntu use the following command
Install Vagrant with this command
sudo dpkg -i vagrant_2.1.2_x86_64.deb
Now after Vagrant is installed you need to install virtualbox, to be able to create a development environment, use these commands to download and install virtualbox.
wget -c https://download.virtualbox.org/virtualbox/5.2.14/virtualbox-5.2_5.2.14-123301~Ubuntu~xenial_amd64.deb
sudo dpkg -i virtualbox-5.2_5.2.14-123301~Ubuntu~xenial_amd64.deb
sudo apt-get install -fy
You are ready now to create a development environment, no need to install anything or manually download an ISO for the VM, let’s get started.
Use these commands to create and start the first development environment in Vagrant which contains a single Ubuntu 16.04 VM.
vagrant init ubuntu/xenial64
The first command initializes a Vagrantfile in current directory, which contains instructions to run a VM with Ubuntu 16.04 installed in it, the second command runs the VM.
You can connect to the VM using
I am not going to describe anymore about Vagrant, as this is out the scope of this article.
Packer is a tool to create pre-configured machine images to be used in creating new VMs from them, packer can help to create a machine image for development environment and use the same image for production environment.
Sometimes you need to create a new VM with some software pre-installed in it and configured in your own way, you can use vagrant to install and configure the VM each time it boots up but you may want to create a new vagrant box that has the software installed and pre-configured already without the need to install it again, here comes packer into play.
You can create a new vagrant box using packer then use vagrant to boot the VM out of the new box as you used it to boot an Ubuntu 16.04 Server.
Pakcer is not tied only to vagrant and virtualbox, you can use it to create an AMI (Amazon Machine Image) configured the way you want it, in this article we will only describe using packer to create a new vagrant box for you yo use it.
The next sections highlight the required steps to create the box starting with an empty Ubuntu 16.04 Box.
Start a new Ubuntu 16.04 VM using vagrant
Execute these commands to create, start and stop an Ubuntu 16.04 VM using vagrant
mkdir -p ~/Vagrant/UbuntuXenial
vagrant init ubuntu/xenial64
Now we need to setup a password for
ubuntu user and install java on the VM using these commands
sudo passwd ubuntu
sudo apt update && sudo apt install default-jdk default-jre -y
We need to stop the VM to be able to export it in the next step.
Export virtualbox vagrant box
Now open the virtualbox GUI and select the newly created VM, it should have a name
UbuntuXenial_default_1532459730905_63441 the number on your machine will
Once the VM is selected click File –> Export Appliance, Choose
Open Virtualization Format 2.0
Format DropDown Menu and enter the path where you want to save the file then click
Now after the VM is exported we can use packer to create a vagrant box from it, this box will have java pre-installed
Create a new vagrant box and provision it
Create a directory to contain packer files in it.
mkdir -p ~/packer/java
Create a new file called
java.json with the following content
"source_path": "[[ OVA_PATH ]]",
"ssh_password": "[[ UBUNTU_PASSWORD ]]",
"shutdown_command": "echo 'packer' | sudo -S shutdown -P now"
"inline": "sudo adduser --gecos '' --disabled-password vagrant && sudo mkdir /home/vagrant/.ssh && sudo chown vagrant:vagrant /home/vagrant/.ssh"
Make sure to replace
"[[ OVA_PATH ]]" and
[[ UBUNTU_PASSWORD ]] with the path you selected in the previous step and the password you set for ubuntu user.
This file has three sections:
- builders: This section specifies packer input, here we are using
virtualbox-ovfbuilder which uses a virtualbox OVF file as an input, the
source_pathoption tells where the file is on the system and the SSH options are needed to access the VM.
- provisioners: These are used to provision the VM after it is created we are using
- A shell provisioner which executes a single command to create a user called vagrant this user is used by default in vagrant to connect to a newly created VM.
- A file provisioner This copies a file into the VM.
- A shell provisioner this one executes a script called
vagrant.shwhich copies the file you inserted into the VM recently using file provisioner to the authorized_keys file for vagrant user and also gives this user passwordless sudo ability.
- post-processors: We are using one post-processor called
vagrantto convert the provisioned VM to a vagrant box.
We need to provide two more files before running packer, the first one is called
vagrant.pub which is the public key to insert into the VM this public key is used
by vagrant when it connects to a VM for the first time after successful connection
it replaces it with a more secure key pair because the private key for this public
key is available to the public, you can download the file with this command
The other file is called
vagrant.sh which is a simple shell script here it is:
# Copy authorized_keys file
sudo cp /tmp/authorized_keys /home/vagrant/.ssh/authorized_keys
# Fix permissions
sudo chown vagrant:vagrant /home/vagrant/.ssh/authorized_keys
# Enalble passwordless sudo for vagrant user
sudo tee -a /etc/sudoers.d/vagrant >/dev/null <<'EOF'
vagrant ALL=(ALL) NOPASSWD: ALL
Now you are ready to build the vagrant box with this command
packer build java.json
Once the build is over you will see output like this
==> Builds finished. The artifacts of successful builds are:
--> virtualbox-ovf: 'virtualbox' provider box: packer_virtualbox-ovf_virtualbox.box
packer_virtualbox-ovf_virtualbox.box the vagrant box we need, in the next
and last step we will add this box to vagrant.
Add the new vagrant box to vagrant and test it
To add the box to vagrant execute this command
vagrant box add --name ubuntu-java packer_virtualbox-ovf_virtualbox.box
Make sure to replace
packer_virtualbox-ovf_virtualbox.box in case your output
was different from mine.
Now we will test the new vagrant box by creating a new vagrant VM and checking if it has java pre-insatlled on it, use these commands:
mkdir -p ~/Vagrant/Java
vagrant init ubuntu-java
These commands create a VM from
ubuntu-java box, checks if java is installed in it
and then stopping the VM.
In this tutorial we learned about vagrant and packer and how we can use them to create pre-configured VMs to our needs, these VMs help new developers to get started quickly in new projects and also help to maintain a single source for configuration in the VMs used for development which minimizes the risks of using different environments or configurations when working on projects.
I hope you enjoyed it, any feedback will be highly appreciated you can use the comment section below or the ChatBot or email me directly at email@example.com.