Neither the blkid or the UUID internal to mdadm work to automount for some reason in Debian partprobe doesn't work but was a good suggestion from: http://pato.dudits.net/2008/11/03/special-device-uuidxxxxxxxxxxxxxxxx-does-not-exist-especially-with-lvm mount: special device /dev/disk/by-uuid/431b9b96-29e8f298-e89bd504-7065bddd does not exist mdadm -D /dev/md_d12 mdadm: metadata format 00.90 unknown, ignored. /dev/md_d12: &nb........

I separated the 2 drives in the RAID 1 array. 1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated). I wonder how mdadm will handle this: usb-storage: device scan complete md: md127 stopped. md: bind md: md127: raid array is not clean -- starting background reconstruction raid1: raid set md127 active with 1 out of 2 m........

Create New RAID 1 Array: First setup your partitions (make sure they are exactly the same size) In my example I have sda3 and sdb3 which are 500GB in size. mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3 mdadm: array /dev/md2 started. Check Status Of The Array *Note I already have other arrays md0 and md1. You can see below that md2 is syn........

Which one does the OS care about? blkid says the UUID is "787f1fa4-b010-4d77-a010-795b42884f56" while md insists its UUID is "4d96dd3b:deb5d555:7adb93cb:ce9182d9" When in doubt, do we assume the OS takes the one from blkid? /dev/md0: UUID="787f1fa4-b010-4d77-a010-795b42884f56" TYPE="ext3" [root@localhost ~]# mdadm -D /dev/md0 /dev/md0: Version : 0.90 &........

I successfully created a single RAID 1 partition which includes /boot inside it and my root directory through the Debian installer. It said GRUB installed successfully but when I try booting the OS it seems GRUB can't read anything. When trying to boot from GRUB GRUB Loading stage 1.5. GRUB loading, please wait... Error 2 I get "Error 2" when trying to boot Debian. I also notice from a LiveCD that........

mdadm --assemble --scan mdadm: /dev/md/diaghost05102010:2 has been started with 2 drives. mdadm: /dev/md/diaghost05102010:1 has been started with 2 drives. mdadm: /dev/md/diaghost05102010:0 has been started with 2 drives. -bash-3.1# cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid6] [raid5] [raid4] [multipath] md125 : active raid1 sda1[0] sdb1[1] 14658185 blocks super 1.2........