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
<snip>
I sympathize. I wanted to use full disk RAID, too. I thought that
<snip> 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?
Yup.
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....
mark