virtualbox.org

The installation of my Ubuntu 12.04 VMs is driven by vagrant-vbguest, which is trying to execute: "/mnt/VBoxLinuxAdditions.run --nox11"
However, this is failing because X is not installed. I didn't encounter this in any previous version (4.2.10, for example). Is this a bug with the GuestAdditions installer or is it an issue with vagrant-vbguest not knowing how to install 4.2.12's Guest Additions?

# /mnt/VBoxLinuxAdditions.run --nox11
Verifying archive integrity... All good.
Uncompressing VirtualBox 4.2.12 Guest Additions for Linux............
VirtualBox Guest Additions installer
Removing installed version 4.2.12 of VirtualBox Guest Additions...
Copying additional installer modules ...
Installing additional modules ...
Removing existing VirtualBox DKMS kernel modules ...done.
Removing existing VirtualBox non-DKMS kernel modules ...done.
Building the VirtualBox Guest Additions kernel modules ...done.
Doing non-kernel setup of the Guest Additions ...done.
You should restart your guest to make sure the new modules are actually used

Installing the Window System drivers ...fail!
(Could not find the X dot Org or XFree86 Window System.)
# echo $?
1

What you see is normal. Of course the x windows fails because you do not have it. The clipboard and shared folders should work though.

Is there a command to install additions but not error out if X is not installed so that it behaves like 4.2.10 and previous versions did?

I don't remember a single version since 1.4 that didn't tell you that the windows service was not going to be installed when x did not exist on the guest.
using the --nox11 switch allows the install to complete and not worry about the missing x window.