[linux-lvm] How to transit from Linux 2.4 to 2.6 with LVM in play?

[Patrick Caulfield]

On Sat, Oct 04, 2003 at 05:12:08AM -0500, Mark H. Wood wrote:
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> On Tue, 30 Sep 2003, Patrick Caulfield wrote:
> [snip]
> > If not then you'll need to patch device-mapper into your 2.4 kernel to
> > allow you to run LVM2 on it. (LVM2 will read the LVM1 metadata)
> 
> OK, I hadn't understood that, while LVM2 will read LVM1 metadata, it must
> read them through the device-mapper.  I patched up a 2.4.21 kernel and
> tried again.  But I still get this:
> 
> # ~mhwood/build/LVM2.2.00.07/tools/lvm vgs
>   /proc/lvm/VGs/vg1 exists: Is the original LVM driver using this volume group?
>   Can't lock vg1: skipping
> 
> Well, of course the original LVM driver activated my one and only volume
> group, otherwise /home wouldn't be mounted and the new 'lvm' wouldn't be
> available for testing.  So it seems to mean that "switch between LVM1 and
> LVM2" means "replace LVM1 tools with LVM2 tools and v.v.", not "you can
> use one set to inspect storage objects activated by the other".  The only
> point of compatibility between the two tool sets is that LVM2 tools
> understand the LVM1 on-disk format; they won't run concurrently.
> 

Well, no you can't run two volume manager concurrently. That would be guaranteed
to corrupt your data :-)

The solution (apart from running Debian!) is just to have the tools in two different
directories and switch between them using PATH.

-- 

patrick