The switch device number, xxxx, entered on the VARY SWITCH command is not defined to the z/OS image from which the command was issued.
No system changes were made.
Verify that the switch device number was entered correctly and retry the command. You can check the device number with the D M=DEV(xxxx) command.
Input/Output Supervisor (IOS)
IOSVVSWP, IEEVCNF1, IEEVCONF