RAID questions (was Re: [TriLUG] Re: Dieing hard drive?)

[Aaron S. Joyner]

William Sutton wrote:

>I've been lurking here watching this thread develop, so I have some 
>questions I'd like to pose to those of you with more expertise than I :) 
>
>I have a spare system based on an Abit VP6, dual PIII 750, 512 MB RAM, 
>etc, etc, that I've been piecing together.  After much diddling I've 
>decided to give it to my parents as an upgrade for their PII 233 Compaq.  
>This being for my parents, it'll need some variant of Windows (before all 
>of you zealots on the list chime in, this question is still on-topic as 
>far as the RAID thread goes, so please don't flame me).
>
>I'd planned on using the board's on-board RAID features so that they have 
>on-system redundancy for the important data (don't care about the OS, just 
>certain files).  I'd also planned on using a couple of 80 GB Maxtor IDE 
>drives (the on-board controller is IDE).
>
>Questions:
>1. Is RAIDing this puppy even a logical decision?
>  
>
Sure, but don't forget that RAID only protects you against down time in 
case of drive failure.  It does not protect you in the slightest against 
Windows botching the files, your mother inadvertently deleting 
something, etc.  You might consider using one as a "backup" drive for 
the other - use a windows version of rsync and do rolling rsyncs to the 
other drive.  Have it mail the results off-site to you - that way you 
can keep an eye on it in case someone decides to delete the destination 
directory because it was "just taking up space".  That might be a better 
solution to meet your actual goals.

>2. If I do want to use RAID, what level(s) do I want?
>  
>
Probably mirroring.  Two drives means you can't do RAID 5, and I stick 
by my original assessment that you don't want to do RAID 5 in software.  
:)  Also, with Mirroring, the layout of the bits on the disk is truly 
irrelevant - the controller's only job is making sure both disks are 
exactly the same.

>3. Do I want to use the on-board controller (this thread is starting to 
>sound like the answer is no)?
>  
>
Sure, if all you're doing is mirroring, there's no reason not to.   
Stripping and RAID 5 are a whole different matter with controller choice.

>4. If not, how does one implement software RAID on a system as spec'ed 
>above?
>  
>
In Windows - you use a controller.  You can do Software RAID, but I 
don't think you can do it for the boot drive, or if you can it's been so 
long I've forgotten.  Google turned up this article, which is geared 
towards striping, but would apply equally well as a starter for 
mirroring some of your data.

>5. Much earlier in this thread there was discussion of relative quality of 
>older drives vs more recent drives.  For stability and durability in a 
>system of this class (old :) 133 MHz PCI bus) what sorts of disk drives 
>would you recommend?
>  
>
Careful, that's a religious question.  :)  Given availability, I'd say 
go w/ newer drives, and try to pick something with at least a 3yr 
warranty.  You'll probably be fine.  :)

Aaron S. Joyner