Re: lightweight virtualization

Richard Kettlewell <invalid@invalid.invalid> wrote:

Jimmy Logan <punk.book8853@fastmail.com> writes:

I'd like to create some kind of service container on rpi4b which I have,
which would allow me to just install something in a normal way (not
programming the whole installation process like dockerfiles), without
changing anything on the current OS.

 
You don’t need any Dockerfiles to use Docker. So, perhaps Docker will
meet your needs.

Isn't the problem that Docker isn't persistent? Next time the container
is started it loses the state from the previous time - so any changes you
make, starting with installing any packages and then on, have to be done
again?

You can address that two ways.  One is to map volumes into the container so
that they will keep the data on the host filesystem and it'll be there again
when the container restarts.  Or you can make your changes then snapshot the
container ('docker commit') and then launch the snapshot as a new container.

Snapshots may suffice for installing your software in the normal way and
then making a new snapshot which will then contain the software every time
the container is started, but any changes made to the snapshot will be lost.
So you'd have to use volumes to ensure that eg a database persists from run
to run.

When I want persistent containers I use incus; they do say they support
aarch64 so I'm surprised it doesn't work.  If it's not working in Raspberry
Pi OS you could try another Linux distro like Ubuntu.  (Before it was
forked, Incus was originally called LXD and written by Canonical so Ubuntu
was their primary supported platform)

Theo