System Startup, Configuration, and Shutdown Reference Manual (32650-90907)

Chapter 3
System Startup Functions
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3 System Startup Functions
The initial system loader (ISL) provides a command-driven user interface for accessing boot utilities or
issuing ISL commands to display or change system startup functions. When the system is booted from tape
(tape boots), processor-dependent code (PDC) directly loads the ISL. When the system is booted from disk
(disk boots), PDC and input/output-dependent code (IODC) boot the utility MMSAVE, which in turn boots ISL.
When loaded, the ISL displays its revision number and prompts for input:
ISL Revision A.00.43 Apr 12, 2000
ISL>
NOTE The prompt changes to ISL>, indicating the ISL is active.