Installing VirtualBox Guest Additions

I've always had issues installing the guest additions and always had issues running the installer from the cdrom, so...

Copy the contents of the cdrom to another location, something like;

mkdir /tmp/guest && cp -R /media/cdrom0/* /tmp/guest/

then go to that directory and exectute VBoxLinuxAdditions.run

I've also had issues during the install and this is generally because the Linux Headers or other development tools are not present, so, its best to install them with something like;

apt install -y dkms build-essential linux-headers-generic linux-headers-$(uname -r)

we can check it is installed by running;

lsmod | grep -io vboxguest

which should return one entry and we can then check the details of the module by;

modinfo vbguest

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