You must create at least one state database and at least three state database replicas.  

A state database stores information about disk about the state of your Solaris Volume Manager configuration. The state database is a collection of multiple, replicated database copies. Each copy is referred to as a state database replica. When a state database is copied, the replica protects against data loss from single points of failure. 

For information about creating a state database, see Chapter 6, State Database (Overview), in Solaris Volume Manager Administration Guide.

Solaris Live Upgrade supports only a RAID-1 volume (mirror) with single-slice concatenations on the root (/) file system.

A concatenation is a RAID-0 volume. If slices are concatenated, the data is written to the first available slice until that slice is full. When that slice is full, the data is written to the next slice, serially. A concatenation provides no data redundancy unless it is contained in a RAID-1 volume 

A RAID—1 volume can be comprised of a maximum of three concatenations.  

For guidelines about creating mirrored file systems, see Guidelines for Selecting Slices for Mirrored File Systems.