[CentOS] RAID questions

[Keith Keller]

On 2017-02-15, John R Pierce <pierce at hogranch.com> wrote:
> On 2/14/2017 4:48 PM, tdukes at palmettoshopper.com wrote:
>
>> 3 - Can additional drive(s) be added later with a changein RAID level
>> without current data loss?
>
> Only some systems support that sort of restriping, and its a dangerous 
> activity (if the power fails or system crashes midway through the 
> restriping operation, its probably not restartable, you quite likely 
> will lose the whole volume)

Doesn't mdraid support changing RAID levels?  I think it will even do it
reasonably safely (though still better not to have a power failure!).  I
have a vague memory of adding a drive to a RAID5 and converting it to a
RAID6 but I could be misremembering.

--keith

-- 
kkeller at wombat.san-francisco.ca.us