[CentOS] Software Raids Questions (I have only ever used hardware?)

[Karanbir Singh]

On 28/09/09 02:11, Ross Walker wrote:
>> Eg. to convert this setup into a raid-5 : start with a 1 disk raid-1
>> degraded, move a disks worth of data onto there, bring in the second
>> disk and let them sync into a 'normal' raid1 state, then convert that
>> into a raid-5 with the 3rd disk. then bring in the 4th disk as
>> hotspare.
>>
>> with TiB's worth of data, its not going to be quick.
>
> Can you convert a RAID0 to a RAID5?

How would you create a 1 disk degraded raid0 :) well, you could - but 
you wont get any data onto it! So you would need to start with 2 disks, 
and with that you then need to store 2 disks worth of stuff somewhere 
while this is building[1].

- KB

[1]: there are h/w based cards that are known to convert a raid-0 to a 
raid-1 and then onto a raid-5 and then 6. so there are ways and means to 
implement it.