Forcing a hung console offline or freeing console resources

There are two forms of the RESET command. Use the following form to force a hung MCS, HMCS or SMCS console into the offline state.

 
RESET|E [CN(consname)]

CN(consname)

Specifies the hung MCS, HMCS or SMCS console device that the system is to force into the offline state. The console name can be 2 to 8 characters in length.

After issuing the RESET CN command, you might need to vary the console between the offline state and the console state to complete device recovery. Issue this command only after exhausting all other means of console recovery such as:

Verifying the physical path to the device
Verifying the control unit the device is attached to
If the device is attached to a channel extender, verifying that the channel extender is in working order
Issuing a VARY OFFLINE command that fails

For SMCS consoles you should issue a VARY NET,INACT,ID=consolelu command. If the console is not deactivated, try a VARY NET,INACT,ID=consolelu,I command. If that is not successful, try a VARY NET,INACT,ID=consolelu,F command.

Resetting a console might take up to 30 seconds to complete. If it is taking a long time to process the command, the system may issue this message: IEE059I RESET CN(consname) COMMAND IN PROGRESS, to indicate that the command is in progress but cannot complete quickly. The system will issue this message: IEE712I RESET PROCESSING COMPLETE, after the command finally completes.

Note: The discussion about forcing consoles offline only applies to MCS, HMCS and SMCS consoles. The situation differs when you use RESET CN for subsystem or EMCS consoles:

For subsystem consoles, the RESET CN command marks the console as being unused without notifying the application that might have allocated the console. Therefore, only use RESET CN for subsystem consoles when you have to take the console away from the application or know that the application is no longer active.

For EMCS consoles, the RESET CN command can only be used if the console is inactive. The command cleans up any ENQ resources associated with the console that might have been left outstanding.

For the system console (SYSCONS), the RESET CN command releases storage associated with the messages that have been presented on the system console. Having the system console in PD mode for long periods of time can cause this amount of storage to grow large and CP utilization by the console address space to increase. Using the RESET CN command releases the storage but may cause messages that are displayed on the system console to never be automatically deleted (DOMed) by the system. Operator action at the system console will be needed to manually remove those messages.