[Klug-general] RAID OF DEATH!!!

[Stuart Buckland]

On Thu, 2004-12-02 at 15:10 +0000, Kevin Groves wrote:
> > !! WARNING !! Do not unplug disks without removing them from the array 
> > first, and having your head switched on and in gear and knowing which 
> > physical disk it is you want to unplug from the array. 
> 
> 
> I'm not sure if it's a good thing to remove more than one from an array 
> at a time. I've tested my RAID a few times by just pulling the disks out 
> (these are IBM xSeries hotplug ones so not a problem to remove) and it's 
> all worked. OK most of my machines are mirrored so only one CAN come 
> out. But I seem to remember that, depending on the RAID level and number 
> of disks, more than one drive down at a time can be a problem.
> 


With standard raid levels 0-5 unless you have multi-way mirrors or
hotspare drives then removing more than one drive at a time will take
the array down.

In theory, if you run mirrored-stripes you could afford to lose more
than one drive and remain operational.  The total number you could lose
would depend on how many drives are present in the array and their
configuration.

stu