On Thu, 2006-06-08 at 14:15 -0400, Drew Weaver wrote:
> Software RAID has failed us so many times in the past that I
> would never recommend it to anyone. Things like: the raid breaking for
> no reason and the server continually rebuilding over and over, and once
> a drive does finally die the other drive wasn't being mirrored properly
> (or wouldn't boot even though we manually sync'd the bootloaders as
> suggested.).
>
> It has been nothing but a hassle, so if you need reliable data
> you need to find a card that works for you, I'm not sure why people are
> so ready to suggest software raid when the fact is its pretty
> unreliable.
I've had software raid work very well for years, but mostly on
scsi controllers. I've even hotswapped replacement drives and
rebuilt without shutting down. I like it because it's not unreliable
on my hardware and since I use RAID1 I can recover data from
any single disk by connecting it to any compatible controller. Or
if a motherboard dies I can shove the drives in a spare chassis
without worrying about whether it has exactly the same controller
and raid configuration.
If you have a problem booting, you can boot the 1st install CD
in rescue mode and fix the grub setup - and 'cat /proc/mdstat' will
always show you if the mirrors are active.
I have heard of problems on SATA drives where errors aren't passed
up to the md layer correctly but I don't have any experience with
that myself. I'd probably go with a 3ware controller for SATA.
--
Les Mikesell
lesmikesell at gmail.com