Re: Upgrading a software RAID

[Bill Davidsen <davidsen@tmr.com>]

Maxime Boissonneault wrote:
>
>>>
>>> I can not install more drives in the computer. It is a home theater 
>>> computer in a small case. I was expecting to be able to let the raid 
>>> manage the copies itself.
>>>
>>> If the / was on a RAID5, would it be able to boot with 2 disks ?
>>> If so, is it possible to convert my RAID0 to a RAID5 ?
>>> For example, I could boot on a CD, backup / onto /home, delete the 
>>> RAID0 array and recreate it as RAID5, then restore the backup. Would 
>>> this work ?
>>
>> Based on my testing (somewhat old now) and regular use, I would say 
>> raid10 is probably your best bet. It's fast and secure, and with the 
>> -f2 option for "far" copies it's able to give high transfer rates.
>
> Doesn't RAID10 means RAID 1+0, which requires 4 disks ?
>
No, they are not the same thing, see the mdadm man page for more 
information. The md module does the whole thing for you, you just select 
the layout, and from my experience and discussions here the "-f2" (far, 
two copies) seems the fastest for read and acceptable fast for write.

-- 
bill davidsen <davidsen@tmr.com>
  CTO TMR Associates, Inc

"You are disgraced professional losers. And by the way, give us our money back."
    - Representative Earl Pomeroy,  Democrat of North Dakota
on the A.I.G. executives who were paid bonuses  after a federal bailout.