А как их включить? Погуглил, везде про их установку, но не про включение. И описывается процедура через графический интерфейс virtualbox. А у меня доступ только к командной строке
Start VirtualBox.
Start the host in question.
Once the host has booted, click Devices | Insert Guest Additions CD Image.
Log in to your guest server.
Mount the CD-ROM with the command sudo mount /dev/cdrom /media/cdrom.
Change into the mounted directory with the command cd /media/cdrom.
Install the necessary dependencies with the command sudo apt-get install -y dkms build-essential linux-headers-generic linux-headers-$(uname -r).
Change to the root user with the command sudo su.
Install the Guest Additions package with the command ./VBoxLinuxAdditions.run.
Allow the installation to complete.
Installation generally involves the following steps:
Before installing the Guest Additions, you prepare your guest system for building external kernel modules. This works as described in Section 2.3.2, “The Oracle VM VirtualBox Kernel Modules”, except that this step must be performed in your Linux guest instead of on a Linux host system.
If you suspect that something has gone wrong, check that your guest is set up correctly and run the following command as root:
rcvboxadd setup
Insert the VBoxGuestAdditions.iso CD file into your Linux guest's virtual CD-ROM drive, as described for a Windows guest in Section 4.2.1.1, “Installing the Windows Guest Additions”.
Change to the directory where your CD-ROM drive is mounted and run the following command as root: