[linux-lvm] failing hard drive

[Stuart D. Gathman]

On Thu, 22 Mar 2007, Lamont Peterson wrote:

> If you're not using RAID, might I suggest that you do?  Those 9 disks would 
> make a nice RAID5 or RAID6 array, and LVM works beautifully on top of 
> software RAID, hardware RAID or any combination of both.
> 
> LVM does not provide redundancy (yes, I know it can do mirroring, but I 
> wouldn't suggest that), it's about easily managing lots of storage space.  
> RAID is about reliability/redundancy.  Use the right tool for the right job, 
> and use both tools together to get all the best benefits of both.

In my use, reliability is paramount.  So I prefer RAID1.  You get 
a performance boost for reads as well.  The md based mirrors can be
mounted separately (careful!) if needed for data recovery and bug workarounds.
(E.g. On Centos-3 grub won't install on mirrored boot partition.  So 
unmount md0, setfaulty hdb1, mount hda1 /boot, grub-install, umount hda1,
mount md0, raidhotadd hdb1.)  RAID5 arrays can only be accessed as raid.

-- 
	      Stuart D. Gathman <stuart at bmsi.com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.