Use the DISPLAY U command to help you keep track of the status
(that is, the availability for allocation) of the devices attached
to the system. This command lets you request the status of:
- All devices
- A specific device type
- Online devices
- Offline devices
- Allocation information (that is, jobname and ASID)
- A range of devices
- Automatically switchable devices
- Unavailable devices
The DISPLAY U command can also display the job names and ASIDs
of device users. Knowing the jobs and ASIDs using a particular device
can help you determine if you can or cannot take a particular device
offline.
D U{[,deviceclass][,ONLINE ][,[/]devnum[,nnnnn]] }
[,OFFLINE][,[/]devnum[,nnnnn]]
[,ALLOC ][,[/]devnum[,nnnnn]]
[,AUTOSWITCH|AS][,[/]devnum[,nnnnn]][SYS=sysname]
[,UNAVAILABLE|UNAVAIL][,[/]devnum[,nnnnn]] (See Note)
{,IPLVOL}
{,VOL=volser}
[,L={a|name|name-a}]
|
Note: Supply all commas between DISPLAY U and a specified
operand. For example, DISPLAY U,,OFFLINE.
To compare this DISPLAY U command with the DEVSERV PATHS command,
see Displaying the status of devices and availability of paths.
- U
- The system is to display unit status information about all devices
or about specified devices, including non-supported devices (those
devices defined in the IODF as DUMMY devices) and channel-to-channel
(CTC) links.
- deviceclass
- The device class for which the system
is to display unit status information. You can enter any one of the
following operands for device type:
- CTC — channel-to-channel (CTC) adapters
- DASD — direct access storage devices
- GRAPHIC — graphic devices
- TAPE — magnetic tape units
- TP — communication equipment
- UR — unit record and dynamic switches
- ALL — all above options displayed
(equivalent to specifying DISPLAY U)
- ONLINE
- The system is to display information (in message IEE457I) about
only those devices of the specified device type that are online. If
you do not specify a device type, the system displays information
about all online devices.
- OFFLINE
- The system is to display information (in message IEE457I) about
only those devices of the specified device type that are offline.
If you do not specify a device type, the system displays information
about all offline devices.
- ALLOC
- The system is to display allocation information (in message
IEE106I) for any specified device that is allocated. Allocation information
includes the jobname and address space identifier (ASID) of each job
to which the device is currently allocated.
- AUTOSWITCH or AS
- The system is to display information the coupling facility has about one specific tape device or
all tape devices that are defined as automatically switchable. AUTOSWITCH
is valid only for tape devices (that is, for a deviceclass of TAPE.) If you omit deviceclass,
the system displays information about all automatically switchable
tape devices. If a device is offline to the issuing system, the information
specifies that the device is offline (“OFFLINE” in the STATUS
column) and does not provide any other information about the device.
- UNAVAILABLE or UNAVAIL
- The system is to display information (in message IEE457I) about
the OFFLINE and UNAVAILABLE tape devices. When one or more devices
are offline and unavailable, the UNIT and TYPE are displayed in message
IEE457I. UNAVAILABLE is valid only for tape devices (that is, for
a deviceclass of TAPE.) If you omit deviceclass, the system displays information about
all offline and unavailable tape devices.
- SYS=sysname
- The system is to display information about the status of automatically
switchable devices on the system named sysname.
- IPLVOL
- The system is to display information (in message IEE457I) about the device from which the system was
initially loaded (IPL'ed). For additional IPL information use the DISPLAY IPLINFO command.
- VOL=volser
- The volume serial of the device for which the system is to display
unit status information in message IEE457I.
Note: If you do not specify ONLINE, OFFLINE, or ALLOC, the
system displays status information, without allocation information,
about both online and offline devices.
- [/]devnum,nnnnn
- The system is to display unit status information about devices
starting with device number devnum for nnnnn number
of devices. devnum is a 3-digit or 4-digit hexadecimal device
number, optionally preceded by a slash (/).
If you omit the device
number, the system assumes the starting device number is X'000'.
If you omit the number of devices and do not specify ALLOC, the system
assumes the number of devices is 16. If you omit the number of devices
and specify ALLOC, the system assumes the number of devices is 8.
The system displays status information for primary paths only.
- L=a, name, or name-a
- Specifies the display area (a), console name (name),
or both (name-a) where the display is to appear.
If you omit this operand, the display is presented in the first available
display area or the message area of the console through which you
enter the command.
Note: - If you specify a device number that was not specified in the IODF
during system installation, the display starts with the next higher
device number that was specified.
- For multiple-exposure devices (supported pre-MVS/ESA SP 5.2),
the value you specify for devnum must be the same as that
specified in the IODF.
- For parallel access volumes, if you specify an alias device
number, the system ignores it and starts with the next device number
that is not an alias device number.
- When the system displays the device type for an MCS
or SMCS console as a 3270 model X, HCD identifies it as a 3270 console.
- For autoswitchable devices, a DISPLAY U command without the AUTOSWITCH
parameter may display a volume serial number other than for the currently
mounted volume if the device is assigned to a different system. Use
the AUTOSWITCH parameter to display up-to-date information for such
a device.
Example 1:
To list the status of the first ten (if any) direct access devices
with device numbers of 400 or higher, enter:
D U,DASD,,400,10
Example 2:
To list the users (jobnames and ASIDs) of the first eight allocated
devices with device numbers of A250 or higher, enter:
D U,,ALLOC,/A250,8
Example 3:
To list the status of a device specified by the volume serial number
D72665, enter:
D U,VOL=D72655
Example 4:
To list the status of the automatically switchable tape device
with the device number of 270, enter:
D U,,AUTOSWITCH,270,1
Example 5:
To list the status of the first 16 automatically
switchable tape devices with device numbers of 000 or higher on the
system named GRS127, enter:
d U,,AUTOSWITCH,,,SYS=GRS127