You can upgrade the Solaris OS by using two upgrade methods: standard and Solaris Live Upgrade. A standard upgrade maintains as many existing configuration parameters as possible of the current Solaris OS. Solaris Live Upgrade creates a copy of the current system. This copy can be upgraded with a standard upgrade. The upgraded Solaris OS can then be switched to become the current system by a simple reboot. If a failure occurs, you can switch back to the original Solaris OS with a reboot. Solaris Live Upgrade enables you to keep your system running while you upgrade and enables you to switch back and forth between Solaris OS releases.
For more information about upgrading and the list of upgrade methods, see Upgrade Planning.