I'm trying to create an image of an RHEL 7.6 Raid0 device.
I've eliminated the UUIDs from grub.conf, but the target device is still failing on boot because it's looking for the UUIDs from the source device.
I think the raid configuration is the culprit, because /etc/mdadm.conf contains references to the UUIDs - it looks like this:
# mdadm.conf written out by anaconda
MAILADDR root
AUTO +imsm +1.x -all
ARRAY /dev/md/Volume1_0 UUID=074e9851:5ee0a282:677d450c:fdbe6a69
ARRAY /dev/md/imsm0 UUID=82a99e7a:3e1729ac:3aae2e09:d4c32c2b
This url:
https://www.thegeekdiary.com/redhat-centos-managing-software-raid-with-mdadm/
contains some directions on how to reconfigure the using mdadm, but I haven't been able to figure it out yet.
For example,
mdadm --create --verbose /dev/md0 --level=0 --raid-devices=2 /dev/sda /dev/sdb
gives the message
super1.x cannot open /dev/sda: Device or resource busy
/dev/sda appears to be part of a raid array:
level=container devices=0
partition table exists on /dev/sda but will be lost or meaningless after creating array
/dev/sdb appears to be part of a raid array
continue?
Obviously, I can't continue with this type of message.
The raid array is currently configured in the BIOS. Maybe it would be better to not do it that way, and create it using mdadm?
Edit: More complete info:
I think it's a real hardware card - it's a custom vendor and they don't come cheap. I checked the previous Centos 6.10 version, which was RAID 0, and it had no mdadm.conf. So apparently, RHEL 7.6 creates an mdadm.conf even if it's a hardware setup.
The reason I think RAID is the issue is that the clone works when I set the system up as non-read.
Also, when drops into emergency mode, the console show several warnings such as:
Warning: /dev/disk/by-id/md-uuid-xxxx... does not exist
Warning: /dev/disk/by-id/md-uuid-yyyy... does not exist
Warning: /dev/mapper/rhel-root does not exist
Warning: /dev/rhel/root does not exist
Warning: /dev/rhel/swap does not exist
And the UUIDs there are the same as those on the source system.
