aaccli: what kind of disk is it ?

[Scott Long]

Tom Samplonius wrote:
> On Wed, 23 Jul 2003, Josh Brooks wrote:
> 
> 
>>I have studied the help/usage for aaccli for quite a while, and I cannot
>>figure out how to do two things:
>>
>>a) how can I determine the actual, real size of the disk ?  For instance,
>>I have some 36gig drives that are 36.8 gigs unformatted size, and some
>>that are 36.4, and so on - if I want to buy a replacement drive to, say,
>>rebuild a mirror, I have to get one that is the same size or larger - so
>>how, in aaccli, can I see the actual unformatted size of that disk ?
> 
> 
>   Most RAID devices do rounding:  4, 9, 18, 36, 72, etc.  So if the device
> is a fraction bigger, it just rounds its capacity down to the standard
> size.

Not true.

> Besides, if you are doing RAID1 or RAID5, the controller can only
> use as much capacity as the smallest disk in the set.  So, if you mirror
> a 9GB and 18GB, you will only get a 9GB set.  
> 

The point of the question was that if a failed disk is replaced with one
that is fractionally smaller, it won't work.

Scott