On 7/12/2011 12:00 PM, Mr. B-o-B cried from the depths of the abyss:
> Mike Miller cried from the depths of the abyss...
>
>
>> It gets worse. This time I created two partitions in the RAID 1: / and
>> /swap. That should have worked, but when I get to the part where it
>> wants to start writing to disk, it can't do it. It couldn't install
>> the package manager and it couldn't install GRUB.
>
> Try to do the raid prep/setup outside of the Ubuntu installer first.
>
> This is how I setup software RAID 1's, and this has worked every time
> for me. I have to be honest I haven't done this on Ubuntu, but I did
> just load the latest Ubuntu live cd to check, and all the commands exist
> so this should work fine. I have done this >30 times on Slackware, and a
> handful of times on Centos & Fedora. I actually used a Slackware install
> disk to setup the raid's on Fedora & Centos, but this is not necessary.
> The Ubuntu disk will work just fine.
>
> I personally like fdisk to create my partitions, but can use cfdisk (or
> anything else Ubuntu might have that you like). One disk 1 (lets call it
> /dev/sda) Create at least two partitions (one for swap & one for /).
> Change the types on both partitions to "Linux RAID autodetect" type "FD".
>
> I like to leave a coupe hundred megs fee at the end of the disk just in
> case I need to replace one latter that isn't exactly the same size. This
> of course is optional.
>
> Now copy your partitions to the 2nd drive (lets call it /dev/sdb) like:
> sfdisk -d /dev/sda | sfdisk /dev/sdb
>
> When this command finishes it will display your Raid disk/partition
> scheme. both drives should match.
>
> Next create your raid 1's
> 1st - root partition (or swap depending how you created your partitions)
>
> mdadm --create /dev/md0 --level 1 --raid-devices 2 \
> /dev/sda1 /dev/sdb1 --metadata=0.90
>
> Do the same for your other partition
>
> mdadm --create /dev/md1 --level 1 --raid-devices 2 \
> /dev/sda2 /dev/sdb2
>
> Now format your swap array (assuming your swap is /dev/md1)
> mkswap /dev/md1
>
> Now start your install like normal. You should see /dev/md1 available
> for your swap, and /dev/md0 available for your root.
>
> At this point I must take a step back. I'm old school, and prefer LILO
> on my boxes. There are a few post install steps to config LILO properly.
> I can send those if you are interested.
>
> For GRUB you will need to do the following post install (prior to reboot).
>
> I am guessing that UBUNTU(not sure, don't really use it) will attempt to
> install grub for you(install in to your MBR). If it does it most likely
> will fail (I've been surprised before though, and perhaps those sneaky
> people over at Ubuntu have this figured out). If it fails that is OK.
> Let's just play it safe & assume it's all F-ed up, and we are going to
> make it right.
>
> put grub on disk 1's MBR:
> grub-install --root-directory=/boot /dev/sda
>
> cd /boot/boot/grub
>
> touch menu.lst
>
> Create a menu.lst for GRUB. I usually do something like this:
>
> timeout 10
> title Slackware Linux is better than Ubuntu
> root (hd0,0)
> kernel /vmlinuz root=/dev/md0 ro
> boot
>
> (not sure the naming scheme for Ubuntu, so double check the kernel part
> & make sure to point the root= to the proper /dev/md# for your root
> partition)
>
> Save this, and take a peek at your /etc/fstab file to make sure your
> swap & / are pointing to /dev/md0 & /dev/md1
>
> /dev/md1 swap swap defaults 0 0
> /dev/md0 / ext3 defaults 1 1
>
> OK. Now reboot it, and enjoy the ride.
>
> Hope this helps & Good Luck!
>
> Mr. B-o-B
>

FOR LILO (if anyone else uses it anymore besides me), here is how to 
handle that.

Same as with GRUB, this needs to be completed post-install, but prior to 
reboot - also installed to your disk 1 MBR.

Edit /etc/lilo.conf

add a new line with:

raid-extra-boot = mbr-only

change the "boot" option to point to your raid 1 partition like:

boot = /dev/md0

save & exit

issue the "lilo" command to rewrite it to the MBR.  Reboot & enjoy the ride.


Please note these notes only apply to RAID 1 setups.  RAID 0 & RAID 5 is 
similar, but the config is slightly different.  Just wanted to throw 
that out there.

Mr. B-o-B