Hardware units of the channel or controller classes can be reconfigured locally in the monitor system and in the other guest systems. In the monitor system channels and controllers can also be reconfigured globally (i.e. the reconfiguration applies to other guest systems as well).
The BS2000 reconfiguration commands /ATTACH-DEVICE and /DETACH-DEVICE are used to attach and detach hardware units.
 | No channels are available on SU x86. X2000 emulates devices with a virtual input/output path. |
VMGIORAL system parameter
The system parameter VMGIORAL=YES/NO can be set in the startup parameter service (SYSOPT-CLASS2 parameter set) in any guest system that is not the monitor system. It can also be modified during BS2000 operation by means of the BS2000 command /MODIFY-SYSTEM-PARAMETERS.
VMGIORAL=YES permits the global detachment of a hardware unit in the monitor system and in the relevant guest system. If VMGIORAL=NO is specified, global detachment of a hardware unit is only permitted when the hardware unit has already been detached in the guest system.
 | Global reconfiguration of hardware units is not available on SU x86. The system parameter VMGIORAL has no effect there. |
The global detachment of a channel by means of FORCE=*UNCONDITIONAL-OFFLINE is carried out irrespective of the setting for VMGIORAL.
The global attachment of a hardware unit is always carried out irrespective of the setting for VMGIORAL.
Paths between hardware units (channel controller, channel device, controller device) can be reconfigured locally in the monitor system and in the other guest systems. In the monitor system the paths can also be reconfigured globally (i.e. the reconfiguration applies to other guest systems as well).
The BS2000 reconfiguration commands /INCLUDE-DEVICE-CONNECTION and /REMOVE-DEVICE-CONNECTION are used to connect and disconnect paths.
The BS2000 command /SHOW-DEVICE-CONFIGURATION displays the status of the hardware units and paths in all guest systems.
Reconfiguration in the monitor system
When reconfiguring (attaching and detaching or connecting and disconnecting) channels, controllers and paths, BS2000 operators can control whether reconfiguration is to be carried out locally in the monitor system or (globally) in all active guest systems as well.
Global reconfiguration is controlled by means of the SCOPE operand in the BS2000 reconfiguration commands (see VM2000-specific syntax as of "ATTACH-DEVICE (Attach hardware units)"):
SCOPE=*OWN-SYSTEM-ONLY
Carries out reconfiguration locally in the monitor system.
SCOPE=*VM2000-GLOBAL
Carries out reconfiguration (globally) in all active guest systems.
Global detachment and disconnection (/DETACH-DEVICE and /REMOVE-DEVICE-CONNECTION) can be suppressed or permitted in the guest system by means of the VMGIORAL system parameter (see section "VMGIORAL system parameter").
Global detachment or disconnection (/DETACH-DEVICE or /REMOVE-DEVICE-CONNECTION) for channels (although there is an exception described in Channel reconfiguration below), controllers and paths is only executed when all the guest systems involved can carry out the order.
When a command is executed, the operator is notified by message NKR0180 of the number of active guest systems and the number of guest systems that are involved in reconfiguration.
Channel reconfiguration
The disconnection of a channel at the hardware level (state offline) after its successful detachment in the monitor system (/DETACH-DEVICE) is executed by VM2000 depending on the state of the channel in all active guest systems and on the FORCE operand. The SCOPE operand is irrelevant.
FORCE=*STD / *YES / *NO(...)
The channel is only disconnected at the hardware level once all the active guest systems have detached it (locally or via global reconfiguration). In this case, the state of the channel changes to offline. Otherwise, the operator is informed by message NKR0082.
FORCE=*UNCONDITIONAL-OFFLINE
The channel is always disconnected at the hardware level, even if not all of the active guest systems have detached it. The state of the channel changes to offline.
A channel whose state is offline can no longer be addressed or attached by a guest system.
Moreover, a channel whose state is offline is not connected at the hardware level (its state does not change to online) until it is attached locally or globally in the VM2000 monitor system.
Reconfiguration in the other guest systems
The reconfiguration of hardware units and paths is always carried out locally in the guest systems and has no effect on other guest systems or the monitor system.
Exception
For a VM with the privilege IO-RESET=*YES, VM2000 carries out a reset of the channel at the hardware level if this is requested by the guest system (see "Initializing a VM").
If SCOPE=*VM2000-GLOBAL is specified, it is rejected in a guest system with message NKR0178.