Normally, I create RAID arrays during installation, but I'm trying to add an array to an existing system. The OS (Mint16) is on its own drive. I've added two brand new physical drives to the machine, and I want to create a RAID 1 array out of them.
When I used the installer, there was an option to make a partition a "physical volume for software RAID". There is no such option in fdisk or Gparted, so far as I can tell.
fdisk also complains that
The device presents a logical sector size that is smaller than the physical sector size. So whatever partition came on the drive is less than optimal.
What command should I run on the drives (they are empty and have no data) to create a full drive partition with the right sector size, in preparation for them to be used as a RAID members?
I feel like there's some step that should be run before the
mdadm --create step that preps them to be RAID members and fixes the sector size issues.