IBM OS/390 User Manual

There are several ways to stop or halt the system, and important subsystems.
Here is a simple example of commands to stop the system:

Drain all active JES2 printers, initiators and so on

Stop Time-sharing

Stop VTAM

Stop APPC (if active)

Display active jobs to see what else needs to be stopped

Stop RMF (and any other active subsystems)

Stop JES2 (see options below)

Flush all SMF buffers, LOGREC, Caches and so on to external
DASD

Now you can safely power the processor off or re-IPL.

There are various flavors of the $PJES2 (stop JES2) command:

Stop JES2 after 

″

all available functions are complete.

″ 

This

usually takes forever to drain all the devices, processes, jobs
and started tasks, that were started under JES.

This is quick and the recommended way to stop JES2 if you
know you are going to re-IPL.

Stop JES2 immediately so you can 

″

hot-start

″ 

it without an

intervening IPL.

Some devices such as the system volumes or work packs are permanently
resident, always mounted, and shared amongst users. Devices such as tape
drives are allocated to one job at a time as they are needed. Others, like
printers are managed by JES2 so they can be used by all jobs.

Use the 

″

D U

″ 

command to see the status of various devices by device address

or device type. For example, enter 

″

D U,DASD,ONLINE

″ 

to display online DASD

units and their volume serial numbers.

Use the 

″

D M

″ 

command to see the paths to devices.

Batch jobs and other users allocate devices for their work, and operators may be
prompted to mount or otherwise respond to these requests.

See section 1.8 

″

Interacting with System Functions

″ 

in 

MVS Commands for a

description of Device allocation, Hot I/O detection, and Device 

″

boxing

″. 

Section

1.9 describes the SWAP command to respond to Failing Devices.

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