Why should I use Vagrant instead of just VirtualBox?

I've been using VirtualBox for many years to create a development environment.

A lot of my colleagues are talking about Vagrant and many people seem very excited about it but I just can't seem to grasp the benefits of it.. seems to me like it's a series of new commands to learn in order to do the same things I did with Virtualbox.

With VirtualBox, I install and configure an environment perfectly, then I can package it up as an OVA or whatever and share it with other office users. You can take a snapshot in VirtualBox if something goes wrong.

Puppet and chef aren’t really part of Vagrant, they’re their own thing right?

So yes, what benefits specifically does Vagrant offer over VirtualBox on it's own?

Answer

This is a big question, so I'm going to break it up into three sections.

Vagrant is used to set up one or more virtual machines by:

• Importing pre-made images (called "boxes")


• Setting VM-specific settings (IP address, hostnames, port forwarding, memory, etc.)


• Running provisioning software like Puppet or Chef

Note that it doesn't install software or set up the machine past loading the VM and setting VirtualBox settings. Think of it as a scripting engine for VirtualBox.

Here are some reasons I've seen for using Vagrant over just VirtualBox.

1. Set Up Multi-VM Networks with Ease

Most of the Vagrant power-user content I've read has been about setting up multiple VMs at the same time. Vagrant gives you a single config file to set these up, enabling you to launch all of them with one command.

Say you've configured three VMs to network with each other using static IPs on the 192.168.1.* subnet. You find yourself in a location that is already using that subnet to hand out IP addresses, and your VMs now conflict. With Vagrant, you can simply edit the Vagrantfile and reload the VMs, whereas with VirtualBox you'd have to open the settings for each VM, if not boot each VM and change them inside.

2. Source Control

By putting the settings in a text file, it enables the configuration to be put under source control. Made some changes last week and accidentally broke the image? Just revert the changes and reload the VM. You can accomplish this with VirtualBox snapshots, but it will take up much more space than just a Vagrantfile.

3. Various Platforms

There's a large number of boxes available at sites such as http://vagrantbox.es. This enables you to try various OSes or distributions, applying the same provisioning to set up similar environments. This can help with testing or adding support to new platforms, and would be time-consuming using just VirtualBox.

There are a lot of arguments for using provisioning software, as well as using image snapshots. For additional discussion, I'll point you to Stephen Nelson-Smith's excellent article How to Build 100 Web Servers in a Day.