8.1.2.1 Guest additions on this VM do not match the installed version

Guest additions on this VM do not match the installed version of VirtualBox!

This means the installed box needs updating or a different version of VirtualBox needs to be used.

There is a script in ./provisioning/init.sh that automates the following manual process:

In the past, it was sufficient simply to install the vagrant-vbguest package.

$ vagrant plugin install vagrant-vbguest

However, if that fails:

1. Check the vagrant-vbguest plugin status:

   $ vagrant vbguest --status
   

2. If the guest version does not match the host, do:

   $ vagrant vbguest --do install [ $TARGET ]
   

3. This may fail. Halt and restart Vagrant:

   $ vagrant halt
   

4. Restart Vagrant and check the status again:

   $ vagrant up
   $ vagrant vbguest --status
   

The vbguest plugin host and guest versions should now match.

For further information, see the "Existing VM".