raid1 w/ 3 active mirrors?

I may have missed this is various docs, but is there any way to make a raid1 array which has 3 (or more) active mirrors, rather than 2 mirrors and spares?

Quoted 3 lines · Gordon Mohr

I may have missed this is various docs, but is there any way to make a raid1 array which has 3 (or more) active mirrors, rather than 2 mirrors and spares?

On our machines with software raid, I usually use all available disks to create (small) root filesystem on raid1 - which is 2, 3, 4, 5, or even 8 on one machine. There's no special restriction on number of mirrors in a raid1 set. You create raid1 array on top of N disks exactly the same as you create it on 2 disks.

Quoted 8 lines · Michael Tokarev

Quoted 3 lines · Gordon Mohr

I may have missed this is various docs, but is there any way to make a raid1 array which has 3 (or more) active mirrors, rather than 2 mirrors and spares?

Quoted 5 lines

On our machines with software raid, I usually use all available disks to create (small) root filesystem on raid1 - which is 2, 3, 4, 5, or even 8 on one machine. There's no special restriction on number of mirrors in a raid1 set. You create raid1 array on top of N disks exactly the same as you create it on 2 disks.

How do you make all the disks active mirrors? When I add a third partition to an functioning RAID1 array (mdadm -a), it always enters as a 'spare'. Only after another disk fails out will it be brought into sync with the remaining active partition.

(I'd like the third partition to be brought into sync, and kept in sync, with the other two immediately, so that a fail does not trigger any flurry of activity.)

Thanks,

- Gordon @ Bitzi
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Quoted 5 lines · Gordon Mohr

How do you make all the disks active mirrors? When I add a third partition to an functioning RAID1 array (mdadm -a), it always enters as a 'spare'. Only after another disk fails out will it be brought into sync with the remaining active partition.

Quoted 3 lines

(I'd like the third partition to be brought into sync, and kept in sync, with the other two immediately, so that a fail does not trigger any flurry of activity.)

when you create the array:

mdadm -Cv /dev/md0 -l1 -n10 /dev/sd{a,b,c,d,e,f,g,h,i,j}1