I am not giving to give much details about mirroring the root partition using Solaris Volume Manager, as this is very basic and most administrator knows the concepts.
The below procedure is same for both X86 and SPARC till step 10, as changes at OK prompt are for SPARC only. Also, make sure that both the disks are bootable from OK prompt.
If the second disk is not having the same layout, do it by using fmthard and prtvtoc.
prtvtoc /dev/rdsk/c1t0d0s2 |fmthard -s – /dev/rdsk/c1t1d0s2
Create the metadb.
metadb -a -f -c 2 c1t0d0s7 c1t1d0s7
MIRROR ROOT
1. Backup /etc/system and vfstab.
2. metainit -f d1 1 1 c1t0d0s0 ->You can not unmount root, so use -f to make the SVM device. 1-cloumn and 1-stripe layer.
3. metainit d0 -m d1 -> Attach d1 to mirror d0
4. metaroot d0 -> This updates /etc/system and vfstab file entires for root file system.
5. lockfs -fa
6. init 6
7. metainit d2 1 1 c1t1d0s0
8. metaattach d0 d2
9. Wait for the sync to complete and get the physical path of root disk and root mirror.
10. init 0
OK Prompt changes
OK show-disks
OK devalias
OK nvalias root-disk /pci@1c,600000/scsi@2/disk@0,0
OK nvalias root-mirror /pci@1c,600000/scsi@2/disk@1,0
OK devalias
OK setenv boot-device root-disk root-mirror
OK setenv diag-device root-disk root-mirror
OK setenv usenvramrc true
OK reset-all
OK boot root-disk
OK boot root-mirror
Ramesh Polarapu 