[CentOS] Upgrading system from non-RAID to RAID1

Thu Jan 12 07:43:26 UTC 2023
Michael Schumacher <michael_ml at gmx.de>

> Follow-up question: Is my proposed strategy below correct:
> - Make a copy of all existing directories and files on the current disk using clonezilla.
> - Install the new M.2 SSDs.
> - Partitioning the new SSDs for RAID1 using an external tool.
> - Doing a minimal installation of C7 and mdraid.
> - If choosing three RAID partitions, one for /boot, one for /boot/efi and the third one for the rest, do I go with the default mdraid version, ie 1.2 I believe?
> - Copying the backup above with contents of the the existing disks, ie not just /root and /home but all other directories and files to the new disks from the clonezilla backup. Note that the new disks will be larger.
> - Change the boot sequence in the BIOS and reboot.

I don't know if this is still a problem, but in the past, CentOS was only writing the boot-loader on one of the RAID-disks. If this one would fail, the OS would not boot. So you had to make sure to copy the boot-loader onto all RAID-members.