# metadb -a -f c0t1d0s7
# metadb
flags         first blk      block count
…
a      u         16             8192            /dev/dsk/c0t1d0s7

Note:
The -a option adds the additional state database replica to the system, and the -f option forces the creation of the first replica.

2. Adding Two State Database Replicas to the Same Slice

# metadb -a -c 2 c0t1d0s7
# metadb
flags         first blk      block count
…
a        u         16              8192            /dev/dsk/c0t1d0s7
a        u         8208            8192            /dev/dsk/c0t1d0s7

Note:
The -a option adds additional state database replicas to the system. The -c 2 option places two replicas on the specified slice.

3. To delete state database replicas:

# metadb -d -f c0t1d0s7

Note:
-d specifies to delete a state database replica. -f specifies to force the operation.

Related posts:

1. State Database Replicas Status [metadb]
2. Replaced Failed SVM Mirror Drive
3. Setup Solaris Volume Manager (Raid 1/Mirroring)