On Sat, Apr 3, 2010 at 4:37 PM, Neil Bothwick <[email protected]> wrote: > On Sat, 3 Apr 2010 16:07:06 -0700, Mark Knecht wrote: > >> The install is complete but it won't boot. grub finds the kernel >> and starts booting but then I get the typical VFS file sync error as >> the kernel starts looking for the install on /dev/md3. What I'm not >> understanding is how does the boot process get the information >> required to assemble the RAID device. By hand in the non-RAID install >> I do this: >> >> keeper ~ # mdadm -A /dev/md3 /dev/sdb3 /dev/sdc3 >> mdadm: /dev/md3 has been started with 2 drives. >> keeper ~ # cat /proc/mdstat >> Personalities : [raid1] >> md3 : active raid1 sdb3[0] sdc3[1] >> 52436092 blocks super 1.1 [2/2] [UU] >> >> unused devices: <none> >> keeper ~ # >> >> but when I try to boot the RAID install it says it cannot find /dev/md3. > > You need to set the partition type for the RAIDed partitions to "Linux > raid autodetect". You'll probably then find that the kernel sets the RAID > as /dev/md0, not md3. > > > -- > Neil Bothwick
Tried changing root=/dev/md0. No change. The actual failure message is the fairly standard VFS - Unable to mount root fs on unknown-block(9,0) I can control this using (for instance) title /dev/sda1 Gentoo Linux 2.6.33-gentoo-RAID root (hd0,0) kernel (hd0,0)/boot/bzImage-2.6.33-gentoo-RAID root=/dev/md3 md=3,1,/dev/sdb3,/dev/sdc3 which changes the message to 'unknown-block(9,3)' Since the mknod command for md devices is always 9 1 or 9 3 those match up. Is this saying that the special file thing for 9,0 and 9,3 are missing at boot time? As I posted in the first post the partitions are marked as autodetect, but if it matters I did that late in the process after the RAID was built. keeper ~ # fdisk -l /dev/sdb /dev/sdc Disk /dev/sdb: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0xa06ef201 Device Boot Start End Blocks Id System /dev/sdb1 1 14 112423+ 83 Linux /dev/sdb2 16 538 4200997+ 82 Linux swap / Solaris /dev/sdb3 544 7071 52436160 fd Linux raid autodetect Disk /dev/sdc: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x2ab15637 Device Boot Start End Blocks Id System /dev/sdc1 1 14 112423+ 83 Linux /dev/sdc2 16 538 4200997+ 82 Linux swap / Solaris /dev/sdc3 544 7071 52436160 fd Linux raid autodetect keeper ~ # Answering Albert - I did it with /dev/md3 because that's how the install guide did it: mknod /dev/md3 b 9 3 mdadm --create /dev/md3 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3 >From fstab: /dev/md3 / ext3 noatime 0 1 >From grub.conf: title Gentoo root (hd0,0) kernel /boot/kernel root=/dev/md3 Granted, my kernel line is a little different: root (hd0,0) kernel (hd0,0)/boot/bzImage-2.6.33-gentoo-RAID root=/dev/md3 but I didn't make it up. I just followed the guide. I set the same RAID kernel options as shown in the guide but maybe there is some other requirement not shown in the guide but actually required? The CONFIG_RAID_ATTRS is not discussed for instance:: keeper / # cat /usr/src/linux/.config | grep RAID CONFIG_RAID_ATTRS=m # CONFIG_BLK_DEV_3W_XXXX_RAID is not set # CONFIG_SCSI_AACRAID is not set # CONFIG_MEGARAID_NEWGEN is not set # CONFIG_MEGARAID_LEGACY is not set # CONFIG_MEGARAID_SAS is not set # CONFIG_SCSI_PMCRAID is not set CONFIG_MD_RAID0=y CONFIG_MD_RAID1=y # CONFIG_MD_RAID10 is not set # CONFIG_MD_RAID456 is not set keeper / # Thanks! - Mark
