CHGDEVMLB (Change Device Description (Media Library)) Command Description
CHGDEVMLB Command syntax diagram
Purpose
The Change Device Description (Media Library) (CHGDEVMLB) command changes the device description for a media library device. Refer to the Use tape library article in the Information Center for more tape information.
Restriction: You must have *IOSYSCFG special authority to use this command.
Required Parameters
- DEVD
- Specifies the name of the device description being changed.
- DEVCLS
- Specifies the class of the media library being created.
*SAME: The value does not change.
*OPT: The device is an optical media library.
*TAP: The device is a tape media library.
Optional Parameters
- RSRCNAME
- Specifies the resource name that identifies the hardware that the
description represents.
Note: Use the Work with Hardware Resources (WRKHDWRSC) command with TYPE(*STG) specified to determine the resource name. *SAME: The value does not change.
*NONE: No resource name is specified. A resource name must be provided before the device can be varied on.
resource-name: Specify the name that identifies the media library device hardware on the system.
- ONLINE
- Specifies whether this object is automatically varied on at initial program
load (IPL).
*SAME: The value does not change.
*YES: The device is automatically varied on at IPL.
*NO: This device is not automatically varied on at IPL.
- UNLOADWAIT
- Specifies the amount of time the system waits for another request to use
the mounted volume before unloading the volume if there are outstanding
requests for an available drive.
Note: This parameter is valid only when DEVCLS(*OPT) is specified. *SAME: The value does not change.
*SYSGEN: The system determines the value.
unload-wait-time: Specify the number of seconds to wait. Valid values range from 1 through 120.
- MAXDEVTIME
- Specifies the maximum amount of time a volume can remain mounted in an
internal device if there are requests for other volumes.
Note: This parameter is valid only when DEVCLS(*OPT) is specified. *SAME: The value does not change.
*SYSGEN: The system default value is used. This allows a maximum device wait time to be specified for each library device user rather than the same value for each user of the library device.
max-device-time: Specify the number of minutes a volume can remain mounted. Valid values range from 1 through 60.
- RSCALCPTY
- Specifies the resource allocation priority.
Note: This parameter is valid only when DEVCLS(*TAP) is specified. *SAME: The value does not change.
*JOB: The priority of the job is used as the resource allocation priority.
resource-allocation-priority: Specify the priority this job is given when requesting a resource. Valid values range from 1 (highest) through 99 (lowest).
- INLMNTWAIT
- Specifies the maximum amount of time a request will wait for allocation of
a tape resource for the initial mount.
Note: This parameter is valid only when DEVCLS(*TAP) is specified. *SAME: The value does not change.
*JOB: The allocation wait time is determined by the default wait time attribute of the job requesting the allocation, rounded up to the nearest minute.
*IMMED: The request will not wait for a tape resource to become available.
*NOMAX: The request will wait until a tape resource is available.
initial-mount-wait-time: Specify the number of minutes a request will wait for allocation of a tape resource. Valid values range from 1 through 600 minutes.
- EOVMNTWAIT
- Specifies the maximum amount of time a request will wait for allocation of
a tape resource for the end of volume mount.
Note: This parameter is valid only when DEVCLS(*TAP) is specified. *SAME: The value does not change.
*JOB: The allocation wait time is determined by the default wait time attribute of the job requesting the allocation, rounded up to the nearest minute.
*IMMED: The request will not wait for a tape resource to become available.
*NOMAX: The request will wait until a tape resource is available.
end-of-volume-mount-wait-time: Specify the number of minutes a request will wait for allocation of a tape resource. Valid values range from 1 through 600 minutes.
- GENCTGID
- Specifies how the cartridge identifiers are assigned to each volume for
tape libraries without bar code readers.
*SAME: The value does not change.
*VOLID: Specifies that the volume identifier is used as the cartridge identifier. Cartridge identifiers can be assigned by mounting each volume and reading the volume identifier.
*SYSGEN: Specifies that the system generate the cartridge identifiers for each volume. If system-generated identifiers are used, tape operations must use the generated cartridge identifiers. The cartridge identifiers are assigned sequentially in the form GEN01, GEN02, GEN03, and so on.
- ROBOTDEV
- Specifies the name of the device description representing the robot for
library devices with separate robots.
Note: This parameter is valid only when DEVCLS(*TAP) is specified. *SAME: The value does not change.
*NONE: No robot device description is specified at this time.
robot-device-description: The specified device description is used. A maximum of 2 robot device descriptions can be specified.
- ROBOTHOST
- Specifies the TCP/IP host name or Internet address of the robotic library
manager. A maximum of 2 robot library managers can be specified.
Note: This parameter is valid only when DEVCLS(*TAP) is specified. Note: The host name specified on the ROBOTHOST parameter may fail to communicate with the 3494 tape media library device when the system is a restricted state. When the system is in restricted state, only one TCP/IP interface is allowed to be active on the system. It is possible that the interface brought up to communicate with the MLB device is not one which is able to communicate with the configured Domain Name Server(s). When running in restricted state, store a mapping between the host name and the IP address in the local host table by using the CFGTCP option 10 or ADDTCPHTE command. *SAME: The value does not change.
*NONE: No robotic host is specified at this time.
host-name: The specified name of the robotic library manager. The user can may enter the robot host name by entering the robot host name or the domain qualified robot host name. The domain qualified robot host name allows input of 255 bytes.
host-internet-address: The specified address of the TCP/IP interface. The internet address must be of the form ddd.ddd.ddd.ddd where ddd is a decimal number ranging from 0 to 255. This decimal number should not contain leading zeros. If the internet address is entered from a commnad line, the address must be enclosed in apostrophes.
- LCLINTNETA
- Specifies the local internet address of the interface that is connecting
to the robot library manager. This is the interface the operating system
will start when TCP/IP needs to be started to use the tape media library.
Note: This parameter is valid only when DEVCLS(*TAP) is specified. *SAME: The value does not change.
*NONE: No TCP/IP address is specified at this time.
local-ip-address: Specify the local internet address to be started. The internet address must be of the form nnn.nnn.nnn.nnn, where nnn is a decimal number ranging from 0 through 255. This decimal number should not contain leading zeros. If the local internet address is entered from a commnad line, the address must be enclosed in apostrophes.
- MSGQ
- Specifies the name of the message queue to which messages are
sent.
*SAME: The name of the message queue does not change.
*SYSOPR Messages are sent to the system operator message queue (QSYS/QSYSOPR).
message-queue-name: Specify the name of the message queue to which operational messages are sent.
The name of the message queue can be qualified by one of the following library values:
-
*LIBL: All libraries in the job's library list are searched until the first match is found.
-
*CURLIB: The current library for the job is searched. If no library is specified as the current library for the job, the QGPL library is used.
-
library-name: Specify the name of the library to be searched.
-
- TEXT
- Specifies the text that briefly describes the device. More information is
in Commonly used parameters.
*SAME: The value does not change.
*BLANK: Text is not specified.
'description': Specify no more than 50 characters of text, enclosed in apostrophes.
Example for CHGDEVMLB
CHGDEVMLB DEVD(LIB01) ONLINE(*NO)
This command changes the device description of a media library device named LIB01. The device is changed so that it is not automatically varied on at IPL.
Error messages for CHGDEVMLB