Re: raid10 redundancy

On 5/7/21 5:46 AM, Wols Lists wrote:

On 07/05/21 02:12, d tbsky wrote:

quoted

Adam Goryachev [off-list ref]

quoted

I guess it depends on your definition of raid 10... In my experience it means one or more raid 1 arrays combine with raid 0, so if each raid 1 arrays had 2 members, then it is either 2, 4, 6, etc for the total number of drives.

indeed. What I want to use is linux raid10 which can be used on
2,3,4,5, etc of disk drives. so it is unlike hardware raid 10.

If you're worried about losing two drives, okay it's more disk space,
but add the third drive and go for three copies. Then adding the fourth
drive will give you extra space. Not the best but heigh ho.

Or make sure you've got a spare drive configured, so if one drive fails
the array will rebuild immediately, and your window of danger is minimised.

Cheers,
Wol

I do this for my medium-speed read-mostly tasks.  Raid10,n3 across 4 or 
5 disks gives me redundancy comparable to raid6 (lose any two) without 
the CPU load of parity and syndrome calculations.

Phil