I've read a whole bunch of posts of trying to get your Raid1 to boot up on the second disk if the first one failed. Nothing has failed yet, but I'm trying to test my setup. 2nd drive comes up with grub bash screen.
2 x WD red 3TB drives (mdadm raid1)
I have sda1 & sdb1 (/boot/efi) on their own partition and not in a raid1. I've read the /boot/efi can't be on raid1. Not sure if that's true or not, but for now they are on their each own partition. Maybe that could be my issue? I've read you can do it with /boot and but not with EFI. That's my main question, should I 'dd' the /boot/EFI partitions so they end up having the same UUID?
/dev/sda
GPT fdisk (gdisk) version 0.8.7
Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present
Found valid GPT with protective MBR; using GPT.
Disk /dev/sda: 5860533168 sectors, 2.7 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): A0F00B38-0030-4607-82E7-313822903BF0
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 5860533134
Partitions will be aligned on 2048-sector boundaries
Total free space is 2925 sectors (1.4 MiB)
Number Start (sector) End (sector) Size Code Name
1 2048 249855 121.0 MiB EF00 Ubuntu1
2 249856 5860532223 2.7 TiB FD00 raid1
/dev/sdb
GPT fdisk (gdisk) version 0.8.7
Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present
Found valid GPT with protective MBR; using GPT.
Disk /dev/sdb: 5860533168 sectors, 2.7 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): A7E6C07D-839F-465D-B9CD-47E45CB62125
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 5860533134
Partitions will be aligned on 2048-sector boundaries
Total free space is 2925 sectors (1.4 MiB)
Number Start (sector) End (sector) Size Code Name
1 2048 249855 121.0 MiB EF00 Ubuntu2
2 249856 5860532223 2.7 TiB FD00 raid2
blkid
/dev/sda1: UUID="C70D-A319" TYPE="vfat"
/dev/sda2: UUID="8a62e7a5-e67d-5620-346d-19327a22ac27" UUID_SUB="b1d472cf-cf30-2ddf-5dbf-0a709e179a90" LABEL="HomeServer:0" TYPE="linux_raid_member"
/dev/sdb1: UUID="C70F-2DD1" TYPE="vfat"
/dev/sdb2: UUID="8a62e7a5-e67d-5620-346d-19327a22ac27" UUID_SUB="269b71a5-2faf-3fd5-a33f-2975acae100a" LABEL="HomeServer:0" TYPE="linux_raid_member"
/dev/md0: UUID="Pxo24d-8Phw-GW8b-kzWc-5CCs-I4Zq-Lp43hv" TYPE="LVM2_member"
/dev/mapper/ubuntu-swap: UUID="ddccb365-e251-4ee1-a15c-b58295210885" TYPE="swap"
/dev/mapper/ubuntu-root: LABEL="root" UUID="ebce6c83-50a7-448d-81cd-2a7a5585fa97" TYPE="ext4"
/dev/mapper/ubuntu-nas: LABEL="nas" UUID="c39a16f5-1644-4f6e-9005-1acf094220ca" TYPE="ext4"
I've done a fresh install of 13.10 sever and had to add grub2 to /dev/sdb1
mount | grep sda1
sudo umount /boot/efi
sudo mount /dev/sdb1 /boot/efi
sudo grub-install --bootloader-id ubuntu2 /dev/sdb
sudo umount /boot/efi
sudo mount /boot/efi
That installed grub and added another option to my efi boot mgr. When looking at my /etc/fstab, it can only mount /boot/efi from sda1. If it fails over, how does fstab know to mount /boot/efi from sdb1 instead?
/etc/fstab
# <file system> <mount point> <type> <options> <dump> <pass>
/dev/mapper/ubuntu-root / ext4 errors=remount-ro 0 1
# /boot/efi was on /dev/sdb1 during installation
UUID=C70D-A319 /boot/efi vfat defaults 0 1
/dev/mapper/ubuntu-nas /nas ext4 defaults,acl 0 2
/dev/mapper/ubuntu-swap none swap sw 0 0
Edit:
I've DD sda1 to sdb1 and with the help of boot-repair, have 2 bootable grubs (among hours of trying stuff). Since I DD the partitions, the blkid UUID is the same. Here is my Boot Repair info. http://paste.ubuntu.com/7155022/
Still, when system tries to boot degraded, it just loops on 'Starting system degraded.' Have to use LiveCD and add the harddrive back to array before it can boot degraded.