User`s guide

• Operator interface and subsystem management functions—command line
interpreter (CLI), DUP support for HSJ and HSD30 array controllers, and
HSZterm support for HSZ array controllers
• Local programs
• Error logging and fault management
• Device services functions—SCSI–2 port control firmware
• Value added functions—Data mapping, caching, state change, failover,
storageset member management, and error recovery
Note
This chapter does not attempt to discuss every controller function or
provide complete detail on every topic. For more information please refer
to the StorageWorks Array Controllers HS Family of Array Controllers
Service Manual.
2.2.1 Core Functions
HS operating firmware provides the following core functions:
• Test and diagnostics
• Executive functions
2.2.1.1 Controller Self-Test and Diagnostics
Controller self-test and diagnostics are performed at power-up and determine the
go/nogo status of the controller subsystem. These self-tests include testing of the
cache modules.
Self-test is fault tolerant with respect to the following:
• It removes bad spots in cache memory from further use.
• SCSI–2 ports—Up to five ports (for HSJ40 or HSZ array controllers) or two
ports (for HSJ30 or HSD30 array controllers) can be bad, and the controller
will still initialize.
• Half or all of the cache can be bad, and the controllers will still initialize.
2.2.1.2 Executive Functions
Firmware executive functions act as the operating environment kernel for the
HS array controllers. EXEC functions are common among the different controller
models. EXEC functions control firmware execution with respect to interrupts,
thread control, queuing support, timers, and so forth.
2.2.2 Host Interconnect Functions
The three different host interconnections supported by the HS operating firmware
are CI, DSSI, and SCSI. The following protocols are used between the host and
each HS array controller model:
• Computer Interconnect (CI) for HSJ Array Controllers
System Communication Services (SCS)
Mass Storage Control Protocol (MSCP)
Tape Mass Storage Control Protocol (TMSCP)
Diagnostic Utility Protocol (DUP)
Controller Technical Description 2–13