Configuring a bootloader

[Messyhair42]

I have Ubuntu 12.04 installed in a RAID 1 array on two identical 3 TB drives. when I installed it it failed to install a bootloader. after troubleshooting that issue; see this thread http://ubuntuforums.org/showthread.php?t=1998052 I had a problem with my BIOS not recognizing all my HDD's. after migrating to a new case and a new PSU I believe I have this issue solved, I couldn't get access to one drive but right now it's nonessential so I disconnected it.

I have Ubuntu on a RAID with an instance of GRUB 1.98 on the MBR of a 160GB drive currently as /dev/sdb but there's nothing in its config file. How do I configure a bootloader to point to my RAID? help is appreciated, I've been running from a flash drive since my hard drive crashed six months ago.

[darkod]

You need to use the alternate install cd for installing on fakeraid, it has better support for raid and installs the bootloder better.
With the standard live cd the bootloader often fails.

You can add it now from live mode if you want to.

What you will need to do is:
Boot into live mode, activate the array:
sudo dmraid -ay

Print the list of all devices and partitions:
sudo parted -l (small L)

Note the name of the raid device, something like /dev/mapper/blah_blah. Also be careful because the partitions will be called the same only with something like 'p1', 'p2', etc at the end.

You need to know EXACTLY what is the raid device, and what the partitions on it.

After that simply mount the root partition, lets say in this example it ends with 'p5' and install grub to the raid device (NOT any partition):

sudo mount /dev/mapper/blah_blahp5 /mnt
sudo grub-install --root-directory=/mnt /dev/mapper/blah_blah

That should do it.

[Messyhair42]

Hrm, I have the alternate install CD and it doesn't have a live mode, at least not from the main menu. I do have a flash drive with 12.04 installed so I'm testing it out with that. when I booted I can absolutly confirm that all my attached drives were recognized, however when booting I again got a degraded RAID message (but not from my other flash drive, which recognized the RAID)

here is the part of
sudo parted -l
Model: Linux Software RAID Array (md)
Disk /dev/md0: 3999MB
Sector size (logical/physical): 512B/4096B
Partition Table: loop

Number Start End Size File system Flags
1 0.00B 3999MB 3999MB linux-swap(v1)


Model: Linux Software RAID Array (md)
Disk /dev/md1: 2997GB
Sector size (logical/physical): 512B/4096B
Partition Table: loop

Number Start End Size File system Flags
1 0.00B 2997GB 2997GB ext4


and terminal doesn't accept
sudo dmraid -ay as a valid command


edit: tomorrow I think i'll attempt a new installation of the system on the RAID

[webguy12]

I am having the same problem with the 12.04 server when I set the raid0 when it come to the grub part of the install It wont install it.

I am lost on how to get this to work..

Thanks..