In Sun Microsystems software, STMSBOOT is the command line utility for managing Solaris Multiplexed I/O. This was known as StorEDGE Traffic Manager (STMS) and is now referred to as MPxIO.
The stmsboot program is an administrative command to manage fibre channel devices under Solaris. When enabled, MPxIO will discover multiple paths to the same fibre channel drives and map them as one device under a new device name. This mapping creates a highly-available and multiplexed (trunked and load balanced) storage presentation on the server configured. The stmsboot command automatically updates /etc/vfstab and dump configuration to properly leverage the new device names.
A reboot is required when enabling MPxIO (the system actually reboots twice).