Bug#597181: lvm2: let users override pvcreate checks

[Alasdair G Kergon]

On Fri, Sep 17, 2010 at 12:29:35PM +0200, Marc Lehmann wrote:
> I think pvcreate should have some kind of force option that lets one write
> or restore a pv header no matter what - the tool already has support
> for restore operations, and this should not be thwarted in emergency
> situations.
 
I'm not keen on that as it can make bad situations even worse.
(Some people will still use the force option before they realising they
just wrote to the wrong disk.)

However, we do have a feature planned that will allow pvcreate to back
up any data it overwrites so it can be restored if it later was found it
was run against the wrong disk.  Once pvcreate can be undone, the
consequences of a mistake are less serious and we can consider relaxing
some of these restrictions.

Alasdair