Re: Check support for logical volume management

[Ryan Finnie <ryan@finnie.org>]

On Sat, Nov 21, 2009 at 10:45 AM, Markus Elfring <Markus.Elfring@web.de> wrote:
>> vgchange could load dm-mod, if block devices in /dev trigger this, but
>> there is a recursive dependency because udev does not create the devices
>> unless the module is loaded.
>
> Can anything be improved here so that the device mapper module will
> automatically provide the required interfaces for LVM tools on demand?

Klaus, you may want to take a look at how Finnix handles it in its
autoconfig.  It has a loop of LUKS dm-crypt, LVM and md-raid checks,
and will repeat the process as long as it has something new to do.
That means it should be able to handle setting up stacked block
devices in any combination (LVM on top of LUKS on top of a RAID setup,
for example).  Once it has run out of new block devices to set up, it
moves on to scanning block devices using its equivalent of
scanpartition.

I've had that code in there for a few major versions now, and I've yet
to see it do anything wrong on complex setups.

RF