Hi, I am trying to mirror a 2nd hard drive on SunBlade100 system of similar size to original hard drive. I went through following steps. >Prtvtoc /dev/dsk/c0t0d0s2 > table >fmthard -s table /dev/dsk/c0t1d0s2 >metadb -a -f -c 2 c0t0d0s7 c0t1d0s7 >metainit -a -f >metaroot d0 >vi /etc/lvm/md.tab - Start of /etc/lvm/md------ d10 1 1 /dev/dsk/c0t0d0s0 d20 1 1 /dev/dsk/c0t1d0s0 d0 -m d10 # d11 1 1 /dev/dsk/c0t0d0s1 d21 1 1 /dev/dsk/c0t1d0s1 d1 -m d11 # d12 1 1 /dev/dsk/c0t0d0s3 d22 1 1 /dev/dsk/c0t1d0s3 d2 -m d12 # d13 1 1 /dev/dsk/c0t0d0s4 d23 1 1 /dev/dsk/c0t1d0s4 d3 -m d13 # d14 1 1 /dev/dsk/c0t0d0s5 d24 1 1 /dev/dsk/c0t1d0s5 d4 -m d14 d15 1 1 /dev/dsk/c0t0d0s6 d25 1 1 /dev/dsk/c0t1d0s6 d5 -m d15 - End of /etc/lvm/md------ >cp /etc/vfstab /etc/vfstab.backup Start of /etc/vfstab.ba------ #device device mount FS fsck mount mount #to mount to fsck point type pass at boot options # #/dev/dsk/c1d0s2 /dev/rdsk/c1d0s2 /usr ufs 1 yes - fd - /dev/fd fd - no - /proc - /proc proc - no - /dev/dsk/c0t0d0s1 - - swap - no - /dev/dsk/c0t0d0s0 /dev/rdsk/c0t0d0s0 / ufs 1 no - /dev/dsk/c0t0d0s3 /dev/rdsk/c0t0d0s3 /opt ufs 2 yes - /dev/dsk/c0t0d0s4 /dev/rdsk/c0t0d0s4 /var ufs 1 no - /dev/dsk/c0t0d0s5 /dev/rdsk/c0t0d0s5 /export/home ufs 2 yes - /dev/dsk/c0t0d0s6 /dev/rdsk/c0t0d0s6 /usr ufs 1 no - #/dev/dsk/c0t0d0s7 /dev/rdsk/c0t0d0s7 /unassigned ufs 2 yes - swap - /tmp tmpfs - yes - End of /etc/vfstab.ba------ >vi /etc/vfstab End of /etc/vf------ #device device mount FS fsck mount mount #to mount to fsck point type pass at boot options # #/dev/dsk/c1d0s2 /dev/rdsk/c1d0s2 /usr ufs 1 yes - fd - /dev/fd fd - no - /proc - /proc proc - no - /dev/md/dsk/d1 - - swap - no - /dev/md/dsk/d0 /dev/md/rdsk/d0 / ufs 1 no - /dev/md/dsk/d2 /dev/md/rdsk/d2 /opt ufs 2 yes - /dev/md/dsk/d3 /dev/md/rdsk/d3 /var ufs 1 no - /dev/md/dsk/d4 /dev/md/rdsk/d4 /usr ufs 1 no - /dev/md/dsk/d5 /dev/md/rdsk/d5 /export/home ufs 2 yes - ######################################################################################## #/dev/dsk/c0t0d0s0 /dev/rdsk/c0t0d0s0 / ufs 1 no - #/dev/dsk/c0t0d0s1 - - swap - no - #/dev/dsk/c0t0d0s3 /dev/rdsk/c0t0d0s3 /opt ufs 2 yes - #/dev/dsk/c0t0d0s4 /dev/rdsk/c0t0d0s4 /var ufs 1 no - #/dev/dsk/c0t0d0s5 /dev/rdsk/c0t0d0s5 /usr ufs 1 no - #/dev/dsk/c0t0d0s6 /dev/rdsk/c0t0d0s6 /export/home ufs 2 yes - #/dev/dsk/c0t0d0s7 /dev/rdsk/c0t0d0s7 /unassigned ufs 2 yes - swap - /tmp tmpfs - yes - End of /etc/vf------ After making the above changes in vfstab and md.tab files, system is rebooted successfully and metaattach and metastat commands are run. >reboot >metaattach d0 d20 >metastat d0 >metaattach d1 d21 >metastat d1 >metaattach d2 d22 >metastat d2 >metaattach d3 d23 >metastat d3 >metaattach d4 d24 >metastat d4 >metaattach d5 d25 >metastat d5 The system was rebooted again and in the BOOTPROM mode, alias was made to 2nd disk. ok show-disks ok envalias bootmirror 2nd-drive-address The system was booted from original hard drive and during operation, the original hard drive power is tunred off and system automatically switches to 2nd hard drive, while experiencing a brief system halt. The system continue to operate as usual without any glitch, after the hard drive siwtchover. However during reboot process, system fails to boot with the following error message. Sync failed Thanks. Mohammad.