You can create a namespace on a loopback file interface (lofi) device, rather than creating a global-devices namespace on a dedicated partition. This feature is useful if you are installing Sun Cluster software on systems that are pre-installed with the Solaris 10 OS.
ZFS for root file systems is supported, with one significant exception. If you use a dedicated partition of the boot disk for the global-devices file system, you must use only UFS as its file system. The global-devices namespace requires the proxy file system (PxFS) running on a UFS file system. However, a UFS file system for the global-devices namespace can coexist with a ZFS file system for the root (/) file system and other root file systems, for example, /var or /home. Alternatively, if you instead use a lofi device to host the global-devices namespace, there is no limitation on the use of ZFS for root file systems.
The following procedures describe how to move an existing global-devices namespace from a dedicated partition to a lofi device or the opposite: