[mythtv-users] Hard Disk Upgrade Options with LVM - Raid 5 with Autofs

[Scott]

On Sep 17, 2006, at 2:10 PM, Joel Turner wrote:

> Several months back I wrote regarding upgrading my storage space on
> my myth system. I'm getting ready to proceed.  I've been researching
> my options and I have some other questions. I currently have a 250GB
> and 150GB drive as one logical LVM volume running the xfs file
> system. I'd like to replace the 150GB with a 320GB drive.  Am I
> correct in thinking that I can add the 320GB to my system, add it to
> the current LVM volume group, do a pmove to move the data off from
> the 150GB and then remove it from the volume?  The end result is that
> I'd like to have about 520GB of space for current recordings.

Yes. i did this on my home system (not a myth box) when I replaced  
two 80GB drives with a new 250GB drive. Of course my procedure wasn't  
quite the same as what you describe but from reading what you wrote  
it seems like you've got all the right concepts down.  I found the  
LVM-HOWTO very helpful :)

> Second question.  I have a Silverstone case that can handle up to 6
> internal drives but only has 4 Sata ports.  With my setup outlined
> above I will have three of the bays occupied with my boot drive
> (IDE)  and the two recording drives (SATA).  I'd like to add a Raid 5
> array to the mix. I see my options as:
>
> 1) Add a controller card, 3 drives and go software raid 5
> 2) Add a 3Ware card, 3 drives and go hardware raid 5
> 3) Setup a NAS, Raid 5
> 4) Direct attached e-Sata storage, Raid 5
>
> I'm personally leaning towards 1 or 2. From what I've read in the
> archives it is possible through mdadm to grow a raid array and add
> disks in the future.  I think a 3 raid array is fine to start but
> would like room to expand.  I'm pretty sure I can take my 3 drive
> internal array and move it out of the box if I need to with option 3
> if I want it to grow.  Because the raid array serves as archive
> storage, can I use autofs to mount and unmount it as needed?  I'd
> like to keep down heat and power usage if possible.

Depending on which distro you're running I like the idea of Linux  
software raid for home system. If I was doing it, I would stay away  
from motherboard solutions or anything that would prevent me from  
being able to move the disk array from one motherboard to another.  
You just never know when you'll need to do that to recover data :)  
The idea of using autofs to reduce heat and power sounds reasonable  
but even when the drives aren't mounted they're still spinning idle.  
Consider using hdparm to put them into sleep mode instead. I think  
you could get away with using only hdparm to reduce head and noise  
without the need to use autofs.

--
Scott