[mythtv-users] How to add more recording disk space: Christmas is coming !

[Brad Templeton]

On Thu, Dec 16, 2004 at 07:36:57AM +0000, Terry Barnaby wrote:
> Hi,
> 
> Any ideas on how I can extend the recordings directory disk space
> used by MythTv temporarily?
> 
> I wish to add an extra hard disk to my server, just for Christmas,
> to record extra programs.
> 
> What I would like to do is simply add an extra directory to the
> "Directory to hold recordings" setup option, like:
> 
> /data/video:/extra/video
> 
> Any other ideas, remember this is temporary I don't what to
> mess around with raid or any other more major schemes ?


Myth is not great at this.  I symphathise with the need to punt things,
and so they punted this problem to the lvm system that can be found
in most modern linux kernels.   You need to have it or install it.

I think in the long run this is a poor punt because if people did not
set up their disk with LVM, it's a hard slog to switch things over.

In addition, LVM won't handle the idea of having some control over what
disk programs go on, and of storing programs on a network mounted filesystem
as well as a local one.   This makes some sense.   Also, if you want to
use hard drives as an archive, you would like to tell it to move files
to a given filesystem.

However, I also agree that managing multiple systems, tracking the
free space on each and figuring the right thing to do is also hard.

Anyway, as to your problem -- do you have lvm?  (man lvm)

If you do, did you make your video partition on lvm?  If so, your
problem is easy, mount your new disk, extend your video partition onto
it, then after you delete the shows to make your space requirements
small again, remove the disk from lvm.  It should do it all.

Alas, it can't really remove the disk full of shows to archive.  That's
harder and needs an intermediate disk.

Didn't format with lvm?  There is no quick conversion.   You need
to have a temporary large space to hold your videos.  You would have
do this:

a) Mount your new disk, pvcreate it for lvm.  It has to be big enough to
    hold your existing library.
b) Create a volume group and logical volume on the new disk.  
c) Move them all there, make it your new /video.  This will take a long time
d) Wipe your old video partition and make it lvm.   Add it to your
   volume group, and grow your logical volume.
e) Extend the filesystem you made on the logical volume (you can do this
   with xfs or ext3)

Now you are in business, and can continue with lvm.

If your new disk can't hold all your videos and you can't find temporary
space elsewhere, this becomes harder.  Fortunately new disks are
often larger.   160gb for $50 after rebate at outpost.com.