Subject: Re: [vserver] readonly root
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Wed, 9 Mar 2011 15:14:23 +0100

On Wed, Mar 09, 2011 at 03:02:16PM +0100, Corin Langosch wrote:
> Hi,

> I basically want to have a single vserver installation and start
> it several times using different configuration options (mainly for
> different network settings). Most important, the files should be
> readonly/ immutable from within the vserver instances. 

> What's the best way to achive this?

you can simply mount the filesystem read only or if you are
just interested in protecting the files, use the immutable
attribute, but make sure your userspace can handle that :)

> I assume this should automatically reduce memory usage a lot 
> because the same files/inodes/libs are used/ shared by all 
> instances, right?

if you have one shared mount, yes, definitely, but note
that you can achieve the same degree of sharing with
unification (which doesn't have the drawbacks of ro mounts)

best,
Herbert

> Thanks for any help,
> Corin