[lxc-users] Booting a Freebsd VM inside a container

[Fajar A. Nugraha]

On Fri, Feb 20, 2015 at 12:56 AM, Anjali Kulkarni <anjali at juniper.net> wrote:
> Hi,
>
> The following link mentions booting an Ubuntu VM inside a container:
> (https://www.stgraber.org/2012/03/04/booting-an-ubuntu-12-04-virtual-machine-in-an-lxc-container/)
>
> However I had 2 qs
> 1. If we do boot a VM inside the container as mentioned in the article,
> would it be of any use like a normal VM from the networking perspective?

In "normal" setup, yes. It would use a bridge.

> Since the VM needs emulated interfaces via qemu, it seems having VM like

lxc does not use qemu. kvm and xen hvm does.

> networking(emulated interfaces connecting to linux bridges etc.) working on
> this VM is either not possible or would need some kind of mapping from the
> qemu interfaces to veth interfaces and define the config file accordingly?

what is it that you want to achieve? There are other networking
methods for lxc that does not include bridge if you have a problem
with that (e.g. concerns about packet snooping)

> 2. Is it possible to boot a Freebsd VM image similar to what is described in
> link above?

Short answer: no.
Long anwser: read
http://en.wikipedia.org/wiki/Operating-system-level_virtualization

containers (lxc, solaris zones, etc) uses the same kernel as the host,
so the "OS" running inside the containers must be able to run on
whatever kernel the host is running. There are some cases which might
SEEM like an exception, but in fact still follows that rule:

- running a linux distro on the container with different arch:
https://www.stgraber.org/2012/02/03/ever-wanted-an-armel-or-armhf-container-on-an-x86-machine-its-now-possible-with-lxc-in-ubuntu-precise/
. This is achieved with the help of qemu-user

- running a very old linux distro (e.g. centos3.x) on solaris zones:
http://docs.oracle.com/cd/E19112-01/ctr.mgr11/817-1592/gchhy/index.html
. This is possible since the solaris kernel can emulate certain linux
syscalls

-- 
Fajar