[CentOS] real SATA RAID

[Ian Forde]

On Sun, 2009-02-08 at 15:33 -0600, Sam wrote:
> The software raid in linux with mdadm is very powerful.  Alot of people 
> stay away from software raid because they think that a hardware solution 
> would be easier to work with.  But with a hardware solution, how do you 
> monitor the status of your drives?  There is usually windows software 
> for that but normally a linux client is non existent.  All of the 
> monitoring and management is built into mdadm.  Once you learn it, it is 
> very easy to use and you can move your raid array from system to system 
> as long as mdadm is installed.  You certainly can't move a hardware raid 
>   setup to another machine unless the cards are identical.

While I think that Linux software RAID is both solid and stable, when
running a production environment I'd much rather use hardware RAID with
hot-swappable drives.  Example? Dell PERC RAID.  Yes - historically
there have been problems - but today it's rock solid.  Monitoring it?
Easy - there are Nagios plugins for omreport.  Drive fails?  Pull the
drive and put the new one in.  Nothing else to do.  Same thing with HP
DL-[35]xx class boxes...

And if you're running, say, a farm of a few hundred servers, you can
just have someone go in once a week armed with a list of disks to pull
and replace.

In short, IMHO, hardware RAID with hot-swap capabilities, on proven,
STANDARDIZED hardware makes it easier (and cheaper) to support a larger
number of boxes.  (If you don't have standardized hardware, and tend to
run somewhat of a mishmash, you're probably better off considering
software RAID...)

	-I