Re: [linux-lvm] multiple volumes..

[Jon Bendtsen <jon+lvm@silicide.dk>]

Anders Widman wrote:
> 
> I have a problem which I want to solve as efficiently as possible.
> 
> The problem is that I have 13 drives os various sizes (30-120GB) which
> I want to combine into one (or a few) logical volumes with redundancy
> if one drive would fail.

13 disks... in one computer. How many controllers do you have ??
Are they all filled up ?? aka, using hd<a,b,c,d,e,f,g,h,...>


> How would the smartest layout be? I was thinking about multiple
> partiontions and then combine them into several RAID 5 chains, and
> then use LVM to manage the logical volumes.

And how many disks would you have in your raid5 thingy ?? Way too
many pr. controller i fear. Only run one (active) ide hd pr.
controller. As for scsi, more, but not many more.

Why not use raid1, or possibly, raid0 ontop of raid1?

 
> There is an expamle of my ideas at http://www.tnonline.net/raid-lvm.png
> As you can see there are 8 chains and about 50 GB unallocated data in
> this example. Can I minimize the loss even better?

Yes, you could avoid it.
Run raid1 on much of it, possibly raid0 on top for speed.
The 30GB disk, and the leftovers from the 2*75GB disks, can
with the leftovers from the 120GB disk be turned into raid1
partitions.

 
> Any help or insight in this would be greatly appreciaded

More info about the disks, ide, scsi, mixed, controllers ??




JonB