Example -- SPARC: Creating a Mirror From root (/)

# metainit -f d11 1 1 c0t3d0s0
d11: Concat/Stripe is setup
# metainit d12 1 1 c1t3d0s0
d12: Concat/Stripe is setup
# metainit d10 -m d11
d10: Mirror is setup
# metaroot d10
# lockfs -fa
# reboot
...
# metattach d10 d12
d10: Submirror d12 is attached
# ls -l /dev/rdsk/c1t3d0s0
lrwxrwxrwx   1 root     root          88 Feb  8 15:51 /dev/rdsk/c1t3d0s0 ->
../../devices/iommu@f,e0000000/vme@f,df010000/SUNW,pn@4d,1080000/ipi3sc@0,0/i
d@3,0:a,raw

The -f option forces the creation of the first concatenation, d11, which contains the mounted file system root (/) on /dev/dsk/c0t3d0s0. The second concatenation, d12, is created from /dev/dsk/c1t3d0s0. (This slice must be the same size or greater than that of d11.) The metainit command with the -m option creates the one-way mirror d10 using the concatenation containing root (/). Next, the metaroot command edits the /etc/vfstab and /etc/system files so that the system may be booted with the root file system (/) on a metadevice. (It is a good idea to run lockfs -fa before rebooting.) After a reboot, the submirror d12 is attached to the mirror, causing a mirror resync. (The system verifies that the concatenations and the mirror are set up, and that submirror d12 is attached.) The ls -l command is run on the root raw device to determine the path to the alternate root device in case the system needs to be booted from it.