[lxc-users] Nested containers - lxcbr0 IP allocation

[Mark Clarkson]

On 28/03/15 13:34, Mark Clarkson wrote:
> Hi,
> Instead of doing testing of LXC in a full VM (e.g. virtualbox), I'm
> doing it in a container. This allows me to run alot of heavy software on
> my laptop where a full vm would struggle. This is my lxc-vm.
>
> lxc-vm (default lxcbr0 is 10.0.3.1)
>
> In the lxc-vm I am creating more lxc containers. My lxc-ct's.
>
> lxc-vm
>   '- lxc-ct (default lxcbr0 is 10.0.4.1)
>
> In the lxc-ct I also install lxc since it sets up cgroups for me. In
> these containers I run docker containers. This is lxc-final.
>
> lxc-vm
>   '- lxc-ct
>       '- lxc-final (default lxcbr0 is 10.0.3.1)
>
> In lxc-final the default lxcbr0 is 10.0.3.1, breaking routing back to
> the host. I think lxc chose these bridge addresses, and cleverly chose a
> different one for the nested container.
>
> Instead of lxc-final reverting back to 10.0.3.1, could it choose the
> next number in the third octet? So multiple levels of nesting will
> always work without editing default/lxc-net, for example:
>
> lxc-root - 10.0.3.1
> '- lxc-nest1 - 10.0.4.1
>     '- lxc-nest2 - 10.0.5.1
>        '- lxc-nest3 - 10.0.6.1
>
> Also, I couldn't find where lxc writes /etc/default/lxc-net. Which file
> writes lxc-net?
>

I forgot to say, this is running on Ubuntu Trusty with lxc 1.0.7.