[GLLUG] Link two RAIDs in one LVM?

[Dr. Axel Stammler]

Hi,

I have a 4 TB RAID system (two identical hard disks combined in a RAID-1, created using mdadm). Now, after a few years, this has reached 90% capacity, and I am thinking about first adding another similar 8 TB RAID system and then combining them into one 12 GB RAID 1+0 filesystem. I should be grateful for any tips, especially about buying two 8 TB harddisks.

Which hardware parameters should I look at?

Which method should I use to combine both RAID systems into one?

- linear RAID
- RAID-0
- Large Volume Management (using pvcreate, vgcreate, lvcreate)

Axel