Hardware vs software raid

[Preston Hagar]

On Thu, Oct 20, 2011 at 11:56 AM, Diego Xirinachs <dxiri343 at gmail.com> wrote:
> Again, thanks all for the input,
> Michael, great information! just to be clear, I meant RAID 1 not 0 (little
> typo there). I currently have RAID 1 software raid on a samba server I
> mantain. I think Im going to use the same type for this server (only that
> with hardware RAID) because of the easy troubleshooting in case of failure
> (just replace RAID card and thats it).
> Also, I was wondering if you can provide the Dell mailist list subscribe
> link? or where can I find it?
>
>

We have mainly Dell hardware and used their hardware RAID (PERC cards)
for a while, but have been trying to phase them out in favor of Linux
or FreeBSD software RAID for a while now.  We never saw significant
performance gains (as another poster said, it is often other things
like network that are the bottleneck) and the management was much more
difficult with the PERC cards.

As a simple test, if you can before you go into production, setup your
RAID array in your hardware card, then pull a drive out while the
system is running.  Then try to go through the steps to get it back
fully on line.  Do the same with a software RAID machine.  We always
found software RAID to be much easier.  With most of Dell stuff, it
often unofficially supports Ubuntu, but officially they typically only
support Red Hat enterprise and Suse enterprise.  It will probably work
on Ubuntu, but we have found that, even with the extra paid support
contracts, unless you are running a version of Linux they like, with
their servers, their controller cards, and even their drives,
purchased from them with their firmware, they won't really support you
and will blame it on whatever they can.

We have had many problems with PERC-based hardware arrays not
rebuilding, complaining about drives not matching (even though they
do) or other oddities.  With software RAID, you can throw just about
anything at it and it will make the disks work.

If you are working for a large organization with hundreds to thousands
of Dell servers, I could see going with their hardware RAID.  If you
have a handful of servers (say less than 15 or so), then I would stick
with Software RAID.  You will get much more support from the community
and Wikis than you will from Dell when things go wrong and it will be
much easier to deal with when you have a drive failure and you need to
replace it.

just my 2 cents.

Preston