SCF Reference Manual for SCP

SCP PROCESS COMMANDS
PRIMARY Command
PRIMARY COMMAND
The PRIMARY command causes the backup CPU to become the primary
CPU and the primary to become the backup. This is a sensitive
command.
Considerations
The effect of the PRIMARY command for 6100 family controllers
differs depending on the controller configuration: dual-port
CIU, single-port CIU, or single-board (6105, 3605, 6106, or 3606)
controller. For details, refer to Appendix D of the Subsystem
Control Facility (SCF) Reference Manual .
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