CentOS - Dec 2014 - CentOS 7 install software Raid on large drives error

Greetings -

I am trying to install CentOS 7 into a new Dell Precision 3610.  I have two 
3 TB drives that I want to setup in software RAID1.  I followed the guide 
here for my install as it looked fairly detailed and complete 
(http://www.ictdude.com/howto/install-centos-7-software-raid-lvm/).  I only 
changed the size of the partitions from what is described, but ended up with 
the disk configuration error that won't allow the installation to complete. 
The error is:

You have not created a bootloader stage 1 target device.
You have not created a bootable partition.

So I am clearly missing a step in setting up the drives; likely before 
running the installer.  My disks are blank raw disks right now with nothing 
on them.  Reading the RHEL Storage Admin Guide (Sec. 18.6, Raid Support in 
the Installer) this should be supported, but I am assuming I may need to do 
something different because the drives are greater than 2 TB.  I have a 
SystemRescueCD that I can use GParted to do some setup in advance of the 
installer, but am not sure of what exactly I need to do.

My objective is to RAID1 the two drives, use LVM on top of the RAID, install 
CentOS7 as a KVM host system, with two KVM guests (Linux Mint and Windows 
7).  Can anyone tell me the steps I am missing, or point me to a better 
tutorial than what I have found in my extensive Google searches.  Thanks.

Please cc me directly on replies as I am only subscribed to the daily 
digest.  Thanks.

Jeff Boyce
www.meridianenv.com

On Dec 3, 2014, at 10:38 AM, Jeff Boyce <jboyce at meridianenv.com> wrote:
> My objective is to RAID1 the two drives, use LVM on top of the RAID
btrfs will meet both your functional objectives (mirroring, management, and
expandability) and should be simpler to set up within the CentOS 7 installer.   
It also gets you a more durable filesystem due to features like checksummed
metadata and scrubbing.

This is the first release where that is a supported option, which is why your
search results aren?t pulling up more recommendations for it.

If you?re one of those still nervous about btrfs, it?s been in the stable
kernels since the 2.6 days, added in early 2009.

For RAID-1 on CentOS 7, have a look at the following:
<http://binblog.info/2014/10/25/centos-7-on-md-raid-1/>

It deals with the situation, including mirroring of /boot.  Note
that in my case, I disabled UEFI in the BIOS, so didn't have
/boot/efi come up on autopartition.

That URL also implies a not-stellar assessment of getting help
on this list.  In that particular case, the assessment was IMO
accurate.  ie: If you're going to answer the question, then
answer the question and don't go off on a tangent.

Devin