Keeping guest additions up to date in Vagrant

At work we use Vagrant and Virtual Box to keep our development environments consistent across the team.  I recently updated my Virtual Box environment and ended up getting the following message.

[web] The guest additions on this VM do not match the installed version of VirtualBox! In most cases this is fine, but in rare cases it can
cause things such as shared folders to not work properly. If you see shared folder errors, please update the guest additions within the virtual machine and reload your VM.

Guest Additions Version: 4.2.10
VirtualBox Version: 4.3

To fix this issue easily, enter the vbguest plugin for vagrant.  This plugin will detect that your guest additions is a different version to the version that you are running and will upgrade it on boot for you.

To install (assuming you’re running vagrant > 1.1) simply run the following:

vagrant plugin install vagrant-vbguest

Then the next time you boot it should update for you.