Geoffroy Doucet

After booting in failsafe mode, Solaris wan’t mount automaticly your root filesystem. Sun recommend to break the mirror and boot directly on one side of the mirror.

If found this method can cause more problems then solving the initial problem. For that reason, I found it easier to mount the meta directly.

Here is the steps you should perform:

• Boot in failsafe mode if you are using a new-boot kernel: boot -F failsafe
• Mount one side of the mirror in read-only: mount -o ro /dev/dsk/c0t0d0s0 /a
• Copy the file /a/kernel/drv/md.conf to /kernel/drv/md.conf
• Reload the kernel module: update_drv -f md
• Initialize SVM: metainit -r
• Re-sync the mirror if needed: metasync -r
• fsck the meta if you want
• Mount the meta: mount /dev/md/dsk/d0 /a
• Update the boot archive: bootadm update-archive -R /a
• Umount the root filesystem
• Reboot

Here is an example session:

Executing last command: boot -F failsafe
Boot device: /pci@1f,0/pci@1/scsi@8/disk@1,0:a  File and args: -F failsafe
SunOS Release 5.10 Version Generic_141444-09 64-bit
Copyright 1983-2009 Sun Microsystems, Inc.  All rights reserved.
Use is subject to license terms.
Configuring devices.
Searching for installed OS instances...
/dev/dsk/c0t0d0s0 is under md control, skipping.
To manually recover the boot archive on a root mirror, please refer
to procedure written in this section of the Solaris Administration Guide.
        How to Manually Update the Boot Archive on a RAID-1 (Mirror) Volume
The section is located at URL :

http://docs.sun.com/app/docs/doc/817-1985/ghgnq?a=view

SUNW,eri0 : 100 Mbps full duplex link up
SUNW,eri1 : 100 Mbps full duplex link up
/dev/dsk/c0t1d0s0 is under md control, skipping.
To manually recover the boot archive on a root mirror, please refer
to procedure written in this section of the Solaris Administration Guide.
        How to Manually Update the Boot Archive on a RAID-1 (Mirror) Volume
The section is located at URL :

http://docs.sun.com/app/docs/doc/817-1985/ghgnq?a=view

No installed OS instance found.

Starting shell.
# mount -o ro /dev/dsk/c0t0d0s0 /a
# cp /a/kernel/drv/md.conf /kernel/drv/md.conf
# umount /a
# update_drv -f md
devfsadm: mkdir failed for /dev 0x1ed: Read-only file system
# metainit -r
# metastat -c
d5               m  2.8GB d25 (maint) d15 (maint)
    d25          s  2.8GB c0t1d0s5
    d15          s  2.8GB c0t0d0s5
d4               m  3.0GB d24 (maint) d14 (maint)
    d24          s  3.0GB c0t1d0s4
    d14          s  3.0GB c0t0d0s4
d1               m  2.0GB d21 (maint) d11 (maint)
    d21          s  2.0GB c0t1d0s1
    d11          s  2.0GB c0t0d0s1
d0               m  9.0GB d20 (maint) d10 (maint)
    d20          s  9.0GB c0t1d0s0
    d10          s  9.0GB c0t0d0s0
# metasync -r
# metastat -c
d5               m  2.8GB d25 d15
    d25          s  2.8GB c0t1d0s5
    d15          s  2.8GB c0t0d0s5
d4               m  3.0GB d24 d14
    d24          s  3.0GB c0t1d0s4
    d14          s  3.0GB c0t0d0s4
d1               m  2.0GB d21 d11
    d21          s  2.0GB c0t1d0s1
    d11          s  2.0GB c0t0d0s1
d0               m  9.0GB d20 d10
    d20          s  9.0GB c0t1d0s0
    d10          s  9.0GB c0t0d0s0
# fsck /dev/md/rdsk/d0
** /dev/md/rdsk/d0
** Last Mounted on /
** Phase 1 - Check Blocks and Sizes
** Phase 2 - Check Pathnames
** Phase 3a - Check Connectivity
** Phase 3b - Verify Shadows/ACLs
** Phase 4 - Check Reference Counts
** Phase 5 - Check Cylinder Groups
74831 files, 2955971 used, 6329329 free (3377 frags, 790744 blocks, 0.0% fragmentation)
# mount /dev/md/dsk/d0 /a
# bootadm update-archive -R /a
Creating boot_archive for /a
updating /a/platform/sun4u/boot_archive
15+0 records in
15+0 records out
# umount /a
# init 6

The system is being restarted.
# syncing file systems... done
rebooting...