the 'right' way to rebuild a container

[George Lengel]

Subject:        	Re: the 'right' way to rebuild a container
From:           	Greg Dickie <greg at max-t.com>
To:             	"Glenn L. Wentworth" <gwentworth at acquiremedia.com>
Copies to:      	linux-poweredge at dell.com
Organization:   	Maximum Throughput
Date sent:      	Fri, 15 Oct 2004 16:55:31 -0400

> Errr haven't had to do this with a Dell (Adaptec/LSI) RAID yet but
> for me thats mostly the point of RAID, you don't go down when you
> lose a disk. I'd hope you can safely rebuild on a live system....

I would think the more correct statement is that's the point of 
hotswap drives. The point of RAID is to save all data when a drive 
fails and not need to go to backup tape. However, even with RAID if 
the drive cannot be plugged while running the box, it has to be 
brought down and then the RAID rebuilt upon restart. With 
RAID+hotplug there should be no downtime. Now maybe these days RAID 
implies hotplug also, but I think there are still cases where you 
can have RAID and not use hotplug devices so the computer has to be 
turned off to exchange the faulty drive.


> > If there is not a downside to hot swapping a failed drive while
> > the system is running why does Dell have the support techs tell
> > customers to rebuild the raid array with the machine off-line? 
> > And other than being off-line for 4 hours are there other pros and
> > cons to the two ways of fixing a raid array with a failed drive?

This seems really really silly to me. Why pay for the extra expense 
of a fancy RAID controller and hotswap drives if you do not use the 
capabilities? I would really wonder what that Dell support person 
was thinking.




--------
George Lengel
RHK Technology, Inc.                 
1050 East Maple Road                Tel: (248) 577-5426
Troy, MI 48083  USA                 Fax: (248) 577-5433
http://www.rhk-tech.com             lengel at rhk-tech.com