Unforgiving Software Raid (2.4.20)

[Roger Oberholtzer]

On Tue, 2005-11-01 at 17:48 -0500, Matthew Carpenter wrote:

> Tonight I will be completing the restore-from-scratch process, and I think I'm 
> going to replace the two LVs with straight RAID arrays.  Just better safe 
> than sorry and I simply don't have the time or energy to play with it at this 
> point.

What do you mean 'replace the LVs with RAID'? These are two different
things. Right?

> 
> However, I will be leaving off the secondary backup drive until I can get a 
> beefier powersupply.
> 
> BOTTOM-LINE:  I need to take back my rants against LVM and RAID as they are 
> unsupported at this point.  That doesn't mean they aren't true, just that I'm 
> no longer convinced.

For me, good news. For you, more coffee and, perhaps a whiskey.

> 
> However, I will offer this rant:
> LVM and RAID between different versions are anything but friendly.  eg.  This 
> is a SuSE 8.2 box, running 2.4.20.  When I booted off the SuSE9.0 and 9.1 and 
> Ubuntu cd's I was able to create everything just how I wanted it.  But I had 
> a difficult time getting any of the others to read the drive.  I can 
> understand not going from 2.6 to 2.4, but between the different 2.6 kernels 
> you might think things work.  I suppose this is all based on little 
> experience, but it's been a painful learning process.  Temper that with the 
> fact that in the past 36 hours I have had 2 hours sleep, 2 hours of 
> trick-or-treating, and 30 hours of work.  I'll be the first to tell you that 
> I'm not exactly balanced at the  moment.  Please forgive the ranting.  I'm 
> beat.

This has been a concern of mine. I think I posted a question along these
lines back in the mists of time. Never did get a straight answer. The
main reason I was considering hardware RAID1 is that I would remove that
variable when going to a new release. Of course, then I may need to lay
in a few spare RAID1 controllers in case one dies. I assume that all
RAID1 disks are not interchangeable between the various RAID1
controllers. Then 'only' the LVM compatibility would be needed. Not that
and RAID1 as well.

--

Roger