[dm-devel] HOW to install software to mapped device persistently

[Alasdair G Kergon]

On Thu, Jun 01, 2006 at 02:11:43PM +0400, V.Kukushkin wrote:
> All we know the good way to make read-only ROOT device be read-write  
> looking.
> It is the use of dmsetup in initrd. It works perfect. But ..
 
Depends where the 'read-only' setting is coming from.

LVM?  Use lvchange -pr

dm itself?  (using device vg0-lvol0 as the example)
  'dmsetup info vg0-lvol0 | grep State' shows ACTIVE (READ-ONLY)

Then:
  dmsetup table vg0-lvol0 | dmsetup reload vg0-lvol0; dmsetup resume vg0-lvol0
And to put it back read-only afterwards
  dmsetup table vg0-lvol0 | dmsetup reload -r vg0-lvol0; dmsetup resume vg0-lvol0

Alasdair
-- 
agk at redhat.com