Re: [gentoo-user] Re: About ready to move /usr, /var and /home to LVM.

[covici@ccs.covici.com]

William Kenworthy <billk@iinet.net.au> wrote:

> On Thu, 2012-04-12 at 22:58 +0300, Nikos Chantziaras wrote:
> > On 12/04/12 22:49, Dale wrote:
> > > Howdy,
> > >
> > > Well, it appears we got the init thingy working.  I'm about ready to
> > > move things around since one of my drives is about full and I need a
> > > spare to move things around with.  I use cp -a to copy things while
> > > booted from a USB stick do hicky.  So far, that has always worked and is
> > > pretty fast.  I do have a question tho.
> > >
> > > When I copy this over, do I still need to copy over null, console and
> > > such to /dev?  I know I don't need everything in /dev but do recall
> > > needing those in the past.  Has this changed since I'm using the init
> > > thingy?  Am I forgetting one?  I thought there was three.
> > >
> > > Anything else that could be a gotcha?  I plan to move this twice.  Once
> > > to the spare drive, repartition the OS drive then copy things back over
> > > again.  It's been a while and with LVM about to be used, I hope it is
> > > the last time.
> > 
> > Make sure this is really what you want.  If *any* of the disks in the 
> > LVM goes bad, you lose everything, not just the data on that single disk.
> > 
> > 
> 
> Not necessarily so ... you can remove a failed drive and only lose the
> data on that drive - the data on the other drives is usually accessible.
> If a drive is in the process of failing you have more options to move
> the data to another drive.  If you dont have lvm ... the data on that
> drive is toast anyway.
> 
> Downside, is you have to be aware that you are using LVM and respond
> accordingly ... go at it the wrong way and it will be you who have lost
> the data (on the whole set of disks), not LVM.  Non LVM is simpler, but
> the gain in flexibility offsets that enormously.
> 
> I have used LVM for years now, and have had failed drives, failing
> drives and add/remove drives and have resized partitions quite a few
> times over that period - without losing everything.  Yes, I have
> sometimes lost data on a drive before I could move it off ... but I look
> at it from the point of view that without LVM, I would not have had a
> chance to save what I did manage to get.
> 

I had a bad drive, and I tried to use pvmove, but it stopped when it got
an error and would  not tell me the file it had trouble with nor would
it move any data past that point -- is there a better way to recover
such data?  I simply used the backup to get my data back, rather than
lvm.

-- 
Your life is like a penny.  You're going to lose it.  The question is:
How do
you spend it?

         John Covici
         covici@ccs.covici.com