SYSGEN, or the System Generation Utility, is a utility that facilitates management of system parameters, page, swap and dump files, and other system settings (see Uses below). It resides in SYS$SYSTEM and is invoked with RUN or MCR.
- system parameter modification
- managing devices and device drivers (taken over by SYSMAN in modern versions of OpenVMS)
- creating and installing page, swap and dump files
- managing startup command procedures
System parameters and the site-independent startup command procedure values are stored in a files, and SYSGEN needs to know which file to use for displaying and modifying these values. The following parameter files can be used:
- ACTIVE - the active system parameter value in memory (loaded by default)
- DEFAULT - a parameter set build into SYSGEN that allows the operating system to boot on any standard configuration
- CURRENT - the current system parameter file on disk (SYS$SYSTEM:ALPHAVMSSYS.PAR on Alpha and SYS$SYSTEM:IA64VMSSYS.PAR on Integrity).
- custom - any file specification can be used. Parameter files can be created with the SYSGEN WRITE command.
- OpenVMS System Management Utilities Reference Manual Vol. II (N-Z) for use instructions