F16 - Converting to RAID1

[Brian Hanks]

OK, I'm a long-time RedHat/Fedora user, but some of the recent changes
(grub2, systemd, hal, etc.) are modifying or deprecating my tried and
true methods.   The latest issue I've got is that I want to add a second
drive in a RAID1 config for my main data partitions.   This is something
I had planned all along and thought it wouldn't be a big deal.  I've
done it countless times before.   I've even got much of the work already
done.  There are just a few pieces that have changed and I want to make
sure I get it right the first time.

I recently built a new "main" machine for my home office.  It plays many
roles including that of main Fedora workstation as well as main Fedora
server.   I primarily use this machine to provide server functions but
do use it for things like photo/movie/mp3 processing, Amarok, GIMP,
etc.  I built it right before Christmas with an SSD for everything
except for {swap}, /var, and /data, which is on a separate 2TB drive. 
When originally built it only used one data drive because HDD prices
were high.  A few weeks later I picked up a matching drive on special. 
It's installed, has partitioned, RAIDed (degraded), formatted, and it
contains a copy of the data.   The problem is I'm not 100% sure what I
need to do to get this thing converted over for the reboot.  

The drives are /dev/sda (SSD), /dev/sdb (existing data drive with ext4
partitions), /dev/sdc (new data drive).  Here's what I was planning to do:
1.  Umount the two RAID devices with a current copy of data.
2.  Edit /etc/fstab replacing Device IDs with new RAID devices
(UUID=???? becomes /dev/md?)
3.  Make backup of /boot/grub2/grub.cfg
4.  Make backup of /boot/initramfs-$(uname -r).x86_64.img
5.  dracut --force initramfs-$(uname -r).img $(uname -r)
6.  grub2-mkconfig -o /boot/grub2/grub.cfg
7.  I don't think I need to install grub2 on the new drive because
that's already on the SSD primary drive.
8.  Do I need to remove the "rd.md=0" from /etc/default/grub?  Or will
grub-2-mkconfig fix this?
9.  Reboot and hope it starts with the new RAID devices (did I mention
that /var is on this disk as well?)
10.  Modify partition types of /dev/sdb to fd (linux raid autodetect)
11.  Add /dev/sdb to the RAID1 arrays and let them sync (mdadm --add
/dev/md? /dev/sdc?)


I would appreciate any advice.


Thanks,
-Brian