Subject: Re: [vserver] Using unionfs on guest root
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Tue, 26 Aug 2008 04:33:56 +0200

On Mon, Aug 25, 2008 at 01:43:02AM +0200, Oliver Welter wrote:
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> Hi All,
> 
> I am playing around with aufs (unionfs) and dont find the right way to
> do the following:
> 
> I want to have a readonly root-image and mount a writable partition on
> top of it. I can so so mounting the trees first in the main context and
> than start the vserver, but I want to do it in the context of the guest,
> so it is not visible outside.

> I put the aufs mount in the guest fstab:
> none / aufs dirs=overlay:rootfs=ro 0 0

that's the correct way to do it (fstab.remote for
network related mounts)

> When I launch the guest, I get:
> vcontext(/dev/null) permission denied

looks like your /dev/null is not accessible,
try to add an explicit 'dev' to the fstab,
IIRC, the fstab mounts are executed 'securely'
which means they add 'nodev' if not specified
otherwise ...

> Anybody has a working setup?

no, why would one do that, when there is something
like unification available, with a lot of advantages
over such an overlay setup ...

HTH,
Herbert

> Oli
> - --
> Protect your environment -  close windows and adopt a penguin!
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