[GRLUG] VPS, multiple partitions?

[Adam Tauno Williams]

On Wed, 2013-03-13 at 04:14 -0400, Jeff DeFouw wrote:
> On Wed, Mar 13, 2013 at 12:28:37AM -0400, Dave Chiodo wrote:
> > Ok, I have a VPS server, and it was installed with an "all on one
> > filesystem" partition scheme. I recently decided to pursue changing this,
> > and had the below exchange with the support department at the company that
> > provides my VPS. I beleive they use "Xen" as their VPS service.
> > Is what they are telling me legit? It sounds like BS to me. Why should I
> > not be able to partition the virtual HD any way I want, and if they are
> > baking up an image of the entire virtual HD, why should any changes I make
> > to it prevent their backup from being able to put it back the way it was?
> > Anyway, here's the gist of the exchange, any tips, advice, correction, or
> > support appreciated.
> I have a Linode (a Xen VPS).  I can make partitions through the 
> management web site.  I've never used their backup,

Neither have I.  But VM backup solutions have only a specific use case -
restore from system meltdown.  They are not to be confused with data
backup [making an offline copy of the important bits].  In playing
around with Xen I feel that it confuses these two separate things.

>  but I found this 
> under the Limitations section of the Backup page:
> "The backup system must be able to mount your disk images on the host. 
> If you've used fdisk on your images to create partitions, or created 
> encrypted volumes, or done anything other than use our deployment or 
> disk image creation tools, we won't be able to back up the data. The 
> backup system operates on files, not at the block level. "
> It doesn't say anything specific about restoring partitions, except that 
> only a full restore is possible.

Which sounds normal to me.  Restoring independent partitions is an easy
way to make an incoherent system.   

One of VMware's backup modes also involves 'mounting' block devices and
has the same [roughly] limitations.  This vs the
make-a-copy-of-a-snapshot-of-the-host approach.  Neither is really
useful for data backup, IMNSHO.  'Traditional' backup and restore
solutions [for data] are easier, more reliable, and certainly more
flexible.