Porteus

Hi guys, let's talk about virtualbox in porteus(4).

I've build the vbox-6.1 and vbox-guest modules via the vbox builder.

Obviously i have to activate vbox on the host system to be able to create
virtual machines (VMs).
(Q:)should the vbox guest (additions) module also be activated on the host?

If yes, then it is not the correct way to install the guest-additions (IMO).
AFAIK the guest-additions have to be installed into the running guest-VM.
[ and who wants to pollute the host with all these files and folders?
vbox-guest-6.1-module = 74 directories, 378 files]

Also, the guest-additions.iso is already included in the vbox-module.
So IMO the correct way would be to install the guest-additions from that iso
within a running VM.

BUT -- you can't do this if you install a stock porteus iso into a VM because
there are no tools for compiling included.[devel/crippled sources] - but thats OK,
you just have to find a way to copy these 2 modules into the VM
[ You already have the 2 modules, they were needed to create the vbox module.]

Now what?
Lazy as i am i use iso-master -[ 3.2.2 already has it]- to open the porteus iso,
copy the 2 modules into the Optional folder, save this new iso and install porteus
into a VM using this one.

Now you have them in the porteus-guest-VM and can install the addons from the
included guest-additions-iso.[ in the VM /mnt/sr0 ./VBoxLinuxAdditions.run]

You can delete the 2 modules later or leave them there - these modules are
not activated when booting but useful for many tasks.
[and you never have to search for them again -- LOL.]

Actually the guest-additions are optional. Run an ftp server on your host and you do not need the additions.

Run an ftp server on your host...

Good point - but this will only cover one aspect;
"to exchange files between the host and the guest"

Actually, the guest-additions do a lot more than that..
https://www.virtualbox.org/manual/ch04.html

Actually, the guest-additions do a lot more than that..

That is why I said "... and you do not *need* the additions".
At least for my use case (developing, testing and running live ISOs) the other features as mentioned in your link are dispensable. But YMMV ...