[Leica] Anyone using Drobo

[jbm at jbm.org (Jeff Moore)]

2010-09-11-18:55:20 Frank Filippone:
> 2/4/6 drive capability... with 2TB per drive, this is a lot of storage
> capabillity.
> 
> I know why I would want 2 drives ( in case 1 goes south....) but....
> Why would I want 4 drives ( capability)?  6?
> 
> Anyone have an opinion for an amateur?

When you have a two-drive array configured for redundancy, it's a
mirror: you're using half and burning half as a failsafe.  You get
approximately the usable storage of one of your drives.

Also I've had spotty results with RAID mirrors actually doing what
they should, although I *hope* one of these vendors does the right
thing. 

When you have four drives, and use RAID-5 (or some proprietary
easily-expanded vendor's subflavor like ReadyNAS X-RAID), you get
three drives' capacity and are still burning only one for redundancy.
And the redundant information is spread around so any one of the four
drives can die, and all your info is still available from the other
three.

For home use, I'd consider the ReadyNAS NV+ (4 drives) the high-value
minimum to consider.

The 6-drive arrays (as in the ReadyNAS Pro flavors) can, I'm pretty
sure, be configured with 6 physical disks to give you 5 disks' worth
of storage which should survive one dead disk, or 4 disks' worth of
storage which should survive two simultaneous dead disks.

That, and the ReadyNAs Pro on gigabit ether is fast enough not to be
annoying when you're copying lots of large files around.

 -Jeff