Installing Red Hat on mdadm-multipath device

1) Install RHEL4 on a non-multipath device (e.g. a lv on VIOS1)
2) After the system hast started, map the mpath devices on both vios and rescan the scsi bus in order to "see" them on the linux lpar
3) Create the following partition table on one device using fdisk
1 Type: PrepBoot Size: Between 16 and 32 MB
2 Type: Linux RAID (fd) Size: 100MB
3 Type: Linux RAID (fd) Size: Rest of the volume
4) Set the bootflag for partition 1 (using "a" on fdisk prompt)
5) Create the multipath devices with mdadm -C /dev/md0 -n 2 -l mp /dev/sdb2 /dev/sdc2 and mdadm -C /dev/md1 -n 2 -l mp /dev/sdb3 /dev/sdc3
6) Copy the PrepBoot partition from sda1 to sdb1 with dd if=/dev/sda1 of=/dev/sdb1 bs=1k
7) Create a filesystem on /devmd0 with mke2fs -j /dev/md0
8) Mount /dev/md0 to /mnt and copy everything from /boot to /mnt (in my example). Umount /mnt and /boot and mount /dev/md0 to /boot
9) Change /etc/fstab to reflect this - e.g. /dev/md0 /boot etc.
10) Create /dev/md1 as pv using pvcreate /dev/md1
11) Add the volume to the rootvg using vgextend <Nameofthevg> /dev/md1
12) Copy the lv's using pvmove -n <name-of-the-lv> <source-device> <target-device> (see document for exact usage)
13) Remove the old disk from the vg
14) Remove the disk from the system
15) remove the mapping on vios1
16) restart the system - Enter SMS Menu and configure the boot device order