[CentOS] How to test RAID-5

Fajar Priyanto fajarpri at cbn.net.id
Thu Mar 9 12:00:57 UTC 2006

On Thursday 09 March 2006 06:42 pm, Nick wrote:
> It uses parity information that it stores across all three drives. In
> your setup 1/3 of each drive is used for the parity information.
> Basically any two drives then have enough parity information to recreate
> the date on the third drive. With raid 5 the usable storage is C * (N
> -1) where C is the capacity of the drives and N is the number of them.
> So if you have 3 * 250GB disks the usable storage is 500GB. If two disks
> die at the same time kiss all your data good bye (although this is a
> pretty rare scenario)

What I don't understand is that when it's running with only 2 disks out of 3, 
it seems that it's still running OK.

1. What is the consequences when RAID-5 array runs with 1 lost disk? Will it 
damage the data?
2. What will happen if I copy a large data (say 30MB) into the running array 
with 1 lost disk?

Fajar Priyanto | Reg'd Linux User #327841 | Linux tutorial 
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