[CentOS] CentOS 7 install on one RAID 1 [not-so-SOLVED]

Wed Jan 25 17:51:15 UTC 2017
m.roth at 5-cent.us <m.roth at 5-cent.us>

Gordon Messmer wrote:
> You didn't answer all of the questions I asked, but I'll answer as best
> I can with the information you gave.
Manitu ate my email, *again*.

> On 01/25/2017 04:47 AM, mark wrote:
>> Made an md RAID 0 on the raw disks - /dev/sda /dev/sdb. No partitions,
>> nothing.
> OK, so right off the bat we have to note that this is not a
> configuration supported by Red Hat.  It is possible to set such a system
> up, but it may require advanced knowledge of grub2 and mdadm.  Because
> I sympathize.  I wanted to use full disk RAID, too.  I thought that
Thank you.
>> However, when I bring it up, fdisk shows an MBR with no partitions. I
>> can, however, mount /dev/md127p3 as /mnt/sysimage, and all is there.
> I assume you're booting with BIOS, then?

> One explanation for fdisk showing nothing is that you're using GPT
> instead of MBR (I think).  In order to boot on such a system, you'd need

Nope. fdisk sees it as an MBR. The SSDs are only 128G. They just run the
server, and the LSI card takes care of the 12 hot-swap drives.... <g>
(It's a storage server.)

> a bios_boot partition at the beginning of the RAID volume to provide
> enough room for grub2 not to stomp on the first partition with a
> filesystem.
> The other explanation that comes to mind is that you're using an mdadm
> metadata version stored at the beginning of the drive instead of the
> end.  Do you know what metadata version you used?

I took CentOS 7's default for mdadm.
>> Did I need to make a single partition, on each drive, and then make
>> the RAID 1 out of *those*? I don't think I need to have /boot not on a
>> RAID.
> That's one option, but it still won't be a supported configuration.

Yeah, I see. Well, time to go rebuild, and this time with three separate
RAID 1 partitions....