On 20/01/2014 18:29, Phil Turmel wrote:

Let me clarify:  /dev/md0 should be a v0.90 or v1.0 raid1 for /boot, no LVM.

 >
 > /dev/md1 is an LVM PV for the OS.


Ok.  That means I need physical partitions for those, on each of the 
drives.

Since I am using 3TB drives, I'll need to use a GPT which, if I 
understand correctly, requires to reveal a dummy 'partition' to make 
the BIOS think there is a boot sector thingy there.

So I'm assuming to pre-partition the physical devices this way:

/dev/sd[x]1 - 64k (? I'm checking the docs) empty, for BIOS to see
/dev/sd[x]2 - 128 MB /boot v0.90/v1.0 RAID1, /dev/md0
/dev/sd[x]3 - remainder ~3 TB for LVM, v1.2 RAID1, /dev/md1

and then make the two RAID1s, and then create the LVM.

Having root in an LVM allows strange things like relocating and/or
resizing it on the fly.  Particularly handy if physical access is difficult.

Yes, it was that potential aspect that set me deciding to try your 
approach.  Functional demands on our systems keep changing.

Much appreciated, Ron