[mythtv-users] Network Drive Storage Questions and others.

[jack snodgrass]

On 9/17/06, Douglas Wagner <douglasw0 at gmail.com> wrote:
> All,
>
>       So i've had my MythTV setup now for about 6 months and loving it to
> death.  Wife's happy, i'm happy, it's all good.
>
>  Big problem is I went with a 250g disk for /video, which I knew at the time
> was small.  Amazingly enough (NOT) it's full...gee, couldn't have guessed
> that would happen.
>
>  So, starting to look at a new drive but also starting to re-consider the
> whole structure.
>
>  Currenlty I have a frontend/backend on one computer with the drive
> internal.  Works as a basic Myth box, no questions about that.  I'm starting
> to try to figure out about client / server installs and off computer disk
> storage.
>
>  Networked disk storage: Considering building or having a computer who's use
> is network disk storage.  What i've got right now is IDE (unfortunately it's
> not sata but money doesn't grow on trees and a new computer right now is
> kinda out of the question).  I can go up to 4 disks on the controller i've
> got right now (it's a raid controller).  Is IDE going to cut it across a
> network?  Will a PII 400 cut it for a disk array device for harddrive
> storage of Myth Videos (Don't see why not).  Figuring exports via both Samba
> and NFS...nfs exporting the drive area SHOULD get mytharchiver to make it
> think the files are local.  Is 100 Base T going to do it for streaming the
> myth recordings out to a foreign disk or do I need to go with gigabit? (Yes,
> it's wired)
>
>  Opinoin question: If you were going to build a network drive array right
> now how would you do it?  Stay away from SCSI, I don't think I could afford
> to go there.
>
>  Frontend/Backend: Don't quite have the computer for this yet don't think
> but in the future, what kind of horsepower does the front end / back end
> need?  Do they both need 3g+ CPUs or does one or the other only need
> something significantly slower?
>
>  Thanks for the advice.
>
>  --Douglas Wagner


My NAS box I built is probably over kill.. it's got a P4 3.0 HT CPU
and gigabit ( jumbo frame supported ) NIC. I can copy a 5 gig file
in about 3 minutes.

At the gigabit network speed, there is very little difference
( 15 seconds ) in copying a 5 GB file to a SATA drive -vs- a
Ultra/ATA drive attached to my promise ide controller.

I tried a 400mhz PIII Celeron and it took 11 minutes to copy
the same 5GB file over a gigabit network. I'd like a slower,
cooler running CPU that what I've got, but it was all that I had
in my junk drawer.

IMHO LVM is overhyped. If you lose one drive, you have the
chance of loosing all of your data. Go with single drive partions,
use autofs to mount  / un-mount them and you'll be better off
in the long run. I have an additial script that I'm tunning that will
run hdparm -y on drives after they have been unmounted that
spins down their drives. Since they are unmounted and spun
down, you lessen the chance of data loss if there is a
system failure and you reduce the heat and noise. heat and
noise is a big issue if you have a bunch of drives going in
a small space.

Someone posted about /mnt/store for myth having to be a single,
huge partion. That's not true. I have ( via NAS ) a smallish, 50GB
partion that is always mounted and used as /mnt/store. I then
have additional, autofs mounted drives that I use for permant
storage. myth_archive_job.pl does a nice job of moving stuff
from /mnt/store to the autofs partions and putting in a symbolic
link in /mnt/store. The symbolic link is all /mnt/store needs to
make mythtv happy.


jack