View Full Version : RAID install, not finding kernel

February 5th, 2010, 01:18 AM
i have a gentoo install setup like this.

i have 4 1TB disks, i used the fdisk utility to partition each identically, no special configuration.

so now have

/dev/sda1 /dev/sda2 /dev/sda3 /dev/sda5 /dev/sdd6
/dev/sdb1 /dev/sdb2 /dev/sdb3 /dev/sdb5 /dev/sdd6
/dev/sdc1 /dev/sdc2 /dev/sdc3 /dev/sdc5 /dev/sdd6
/dev/sdd1 /dev/sdd2 /dev/sdd3 /dev/sdd5 /dev/sdd6

and used mdadm like this

mdadm --create --verbose /dev/md1 --level=1 --raid-devices=4 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1
mdadm --create --verbose /dev/md2 --level=5 --raid-devices=4 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sdd2
mdadm --create --verbose /dev/md3 --level=5 --raid-devices=4 /dev/sda3 /dev/sdb3 /dev/sdc3 /dev/sdd3
mdadm --create --verbose /dev/md4 --level=5 --raid-devices=4 /dev/sda5 /dev/sdb5 /dev/sdc5 /dev/sdd5
mdadm --create --verbose /dev/md5 --level=5 --raid-devices=4 /dev/sda6 /dev/sdb6 /dev/sdc6 /dev/sdd6

works fine.

my grub.conf

title Gentoo
root (hd0,0)
kernel /boot/gentoo-2.6.31-r5 root=/dev/md3

In my kernel config, i enabled "autodetect RAID at boot"
grub loads my kernel, then i get a kernel panic.

md: Autodetecting RAID arrays.
md: Scanned 0 and added 0 devices.
md: autorun ... DONE.
VFS: Cannot open root device "md3" or unknown-block(0,0)
Please append a correct "root=" boot option; here are the available partitions:
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

can someone help me?