non root LVM not working with recent initscripts

[Alasdair G Kergon]

On Sun, Apr 03, 2005 at 12:45:55PM +0200, Ronny Buchmann wrote:
> so "/sbin/lvm.static vgscan --mknodes --ignorelockingfailure" complains about 
> failing mkdir (because of read-only fs)

That command has two outputs:
  1. It writes to /etc/lvm/.cache.  [No point if filesystem ro.]
  2. It brings lvm2 nodes into line with the kernel in /dev.


[Assuming /etc isn't on its own partition]
rc.sysinit needs:

  remount / rw

  vgscan --mknodes --ignorelockingfailure
  vgchange -ay --ignorelockingfailure

  raid init if present

  if any raid volumes were found:
    vgscan --mknodes --ignorelockingfailure
    vgchange -ay --ignorelockingfailure

  fsck & mount all non-/

...
clustered lvm initscript:
  initialise locking
  vgchange -ay


The issue here is that everyone with raid suffers from 'vgscan' running 
twice in rc.sysinit.  People have either lvm-over-raid (preferred) or
raid-over-lvm but rarely both: we could do with a way to detect or tell 
the initscripts which is present.


The mkdmnod functionality is now supposed to be built-into lvm2
transparently [inside libdevmapper].
And vgscan functionality (item 1 above) should also be built-in now: 
other lvm2 commands should issue an implicit 'vgscan' whenever they need 
to.  (This is a recent change so there could still be cases it misses.)

Alasdair
-- 
agk at redhat.com