This is perhaps too specific/personal a question for S.O. but here it is:
I've inherited a server currently running a single hard drive, which through default Ubuntu 16.04 server setup, is running its disk in the following partition scheme:
sda1 : 512 Mb : Boot : primary/physical partition sda2 : Rest of Disk : Extended Partition sda5 : Rest of Disk : Logical, Linux LVM Partition
There is one volume group in the LVM, made from only this disk. It is divided into:
swap_1 (2.00 GB) root (remaining space)
The final goal is to move this drive's contents (and structure) onto two, larger, individually bootable RAID1 drives.
That being said, my "goal" is for each new of the new sdb, sdc is to:
/dev/md0 is going to be a raid1 between sdb1 and sdc1, which will be formatted and (hopefully) a copy of sda1. Md0 will not be LVM'd but used directly (so we can boot from it)
/dev/md1 is going to be a raid1 between sdb2 and sdc2. /dev/md1 is going to be used as the only PV for a new VG, divided similarly to above (2GB for swap, and the rest for storage).
So, my hypothetical process involves booting into this system with a recovery CD, setting up md0 and md1, creating the LVM on md1, and copying the data using dd from sda1 to md0 and /dev/vg1/root to /dev/vg2/root, respectively. And of course, installing grub to /sdb and /sdc.
Initial tests are looking promising, but is there a better practice means of doing this?