On 9/3/24 01:31, David C. Rankin wrote:
On 9/2/24 8:15 AM, Paul E Luse wrote:
It shows the RAID level above as 1E which is effectively RAID1 near
layout as described here:
https://raid.wiki.kernel.org/index.php/A_guide_to_mdadm
Thank you for the link Paul,
I've read it, but I'm still confused as to just what that raid was.
Yes, I read that Raid1 2-disk can be the basis of a Raid 4, 5, 6 setup,
but where I'm confused is the output shows:
Secondary Level[1] : Striped
Device Size[1] : 2925241344
Array Size[1] : 46803861504
Which shows the Array size as 46803861504 and Device Size as
2925241344. So the best I can glean from the wiki is that is some type
of Raid0 setup made out of Raid1 mirrors.
Where I also have trouble is with:
Physical Disks : 255
But earlier there was:
Raid Devices[0] : 16 (15@0K 16@0K 17@0K 18@0K 19@0K 20@0K 21@0K 22@0K
23@0K 24@0K 25@0K 26@0K 27@0K 28@0K 29@0K 30@0K)
I guess the 8-bit worth of physical disks that make up 16 raid
devices (or 16 physical disks per-device). I guess there is just no
Cliff's Notes version that outlines all of the ways linux-raid can be
fit together and extrapolated to make all kinds of things. Just glad I
didn't have to work out the command line to replace a disk in that...
It looks like it was a part of an LSI RAID using DDF metadata. You
should be able to find the answers in this spec:
https://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf
Regards,
Artur
