>>-+-/MODIFY-+--+-ABORT--------------------------------+------->< '-/MOD----' +-COMMIT-------------------------------+ '-PREPARE--| A |--+------------------+-' '-LTERM--ltermname-' A: |--+-ALL--+----------+--+----------+--+----------+-------------+--| | '-PASSWORD-' '-TERMINAL-' '-TRANCMDS-' | | .-------------------------------------------------------. | | V | | '---+-ACBLIB--+------+----------------------------------+-+-' | '-BLDL-' | +-FMTLIB--------------------------------------------+ +-MODBLKS--+----------+--+----------+--+----------+-+ | '-PASSWORD-' '-TERMINAL-' '-TRANCMDS-' | '-RACF----------------------------------------------'
Table 76 lists the environments (DB/DC, DBCTL, and DCCTL) from which the command and keywords can be issued.
Command / Keywords | DB/DC | DBCTL | DCCTL |
---|---|---|---|
/MODIFY | X | X | X |
ABORT | X | X | X |
COMMIT | X | X | X |
LTERM | X | X | |
PASSWORD | X | X | X |
PREPARE | X | X | X |
TERMINAL | X | X | |
TRANCMDS | X | X |
/MODIFY controls the modification of IMS resources online. It switches the online environment from the active ACBLIB, FORMAT, MATRIX, and MODBLKS libraries to the inactive libraries containing the new or changed resource descriptions. See IMS Version 9: Administration Guide: System and IMS Version 9: Installation Volume 1: Installation Verification on how to create the inactive libraries before using this command. See IMS Version 9: Utilities Reference: System for information on using the Online Change utility. The descriptions of the resources and parameters for the /MODIFY command are shown in Table 77
The correct sequence for /MODIFY commands is PREPARE followed by COMMIT. If the online change is not to be completed, the /MODIFY ABORT command is used. The /MODIFY PREPARE command specifies which resources are to be changed or deleted. Depending on the parameters entered, the system will initiate quiescing of appropriate resources. COMMIT initiates the changes entered in a preceding PREPARE. If a previously entered /MODIFY PREPARE command is to be canceled, ABORT must be entered.
An IMS automated operator program can issue the /MODIFY PREPARE and /MODIFY ABORT commands, but it cannot issue the /MODIFY COMMIT command. Thus, you can automatically prepare or abort online change.
If this command is used to delete a database, IMS closes the database and makes it unavailable to programs. Also, if the database is authorized for DBRC, /MODIFY unauthorizes it.
Fast Path DEDBs are supported by the /MODIFY command, but Fast Path MSDBs are not supported.
In an IMSplex, /MODIFY is not supported if coordinated online change is enabled.
If ALL was specified on the /MODIFY PREPARE command, the ACBLIB, FMTLIB, and MODBLKS changes must be successful or the /MODIFY COMMIT will be rejected. When COMMIT is successful, the modifications will persist across all IMS restarts. If FMTLIB is entered, most new and in-progress requests will be queued for processing after the /MODIFY COMMIT command is completed.
If MODBLKS or ACBLIB is specified, work in progress in the system for changed or deleted ACBLIB and MODBLKS resources must be completed, or the /MODIFY command is rejected.
/DISPLAY MODIFY is used to display the work that was in progress prior to the entering of /MODIFY COMMIT.
IMS will prevent messages entered from terminals from being queued to transactions, but program-to-program switches from applications can still occur. Therefore, a /DISPLAY MODIFY command can indicate that no work is pending for the resources to be modified or deleted, but the /MODIFY COMMIT might be rejected. If this occurs, the new work must be allowed to complete and then the /MODIFY COMMIT command must be reentered.
/MODIFY COMMIT is rejected if:
Operator action might be required to prevent the preceding conditions. For example, if a program or database is scheduled, the operator should either wait until the program or database is finished before the /MODIFY COMMIT command is entered, or the operator should issue /STOP or /PSTOP for the associated transaction.
If IMS is in an IMSplex and Resource Manager (RM) is using a resource structure, the transactions being added by the online change are registered to RM if they are not already registered to RM. If any error occurs during the CSLRMUPD request to register the transactions, the /MODIFY or INITIATE OLC command will fail and IMS will be in a COMMIT2F state.
If a /MODIFY COMMIT command results in the COMMIT2F state, the command is rejected with a DFS178 message. A DFS3308 message is sent to the system console with the CSLRMUPD return/reason code. The IMS remains in a COMMIT2F state and the /MODIFY cannot be committed or aborted. The IMS must be cancelled and warm started as the online change is not complete.
The parameters in Table 78 are valid with /MODIFY PREPARE. The environments in which the parameters are valid are also shown in Table 78.
Parameter | DB/DC | DBCTL | DCCTL |
---|---|---|---|
ACBLIB | X | X | X |
ALL | X | X1 | X |
BLDL | X | X | X |
FMTLIB | X | X | |
LTERM | X | X | |
MODBLKS | X | X | X |
PASSWORD | X | X | X |
TERMINAL | X | X | |
TRANCMDS | X | X | |
RACF | X | X | |
Note:
|
Related Reading: See IMS Version 9: Administration Guide: System for more information on security definition.
The message DFS3432 RACF PARAMETER INVALID IF RACF DATA SPACE IS USED is issued if the RACF parameter is used on the /MODIFY PREPARE command when the RACF data space is being used. You can use the RACF command SETROPTS RACLIST (classname) REFRESH to refresh the RACF resource profiles in the RACF data space without requiring the IMS applications to suspend work.
Related Reading: See IMS Version 9: Administration Guide: System for more information on security definition.
Related Reading: See IMS Version 9: Administration Guide: System for more information on security definition.
This is an example of a successful PREPARE, COMMIT sequence. First, the command /MODIFY PREPARE ALL is issued.
Entry ET:
/MODIFY PREPARE ALL
Response ET:
DFS3499I ACTIVE DDNAMES MODBLKSA IMSACBA FORMATA MODSTAT ID: 103
Explanation: The modifications are brought online to IMS during a subsequent successful /MODIFY COMMIT command. The ddnames of the active data sets and the current MODSTAT identifier are shown. This message is the normal response.
This is an example of a prepare/commit/abort sequence.
Entry ET:
/MODIFY COMMIT
Response ET:
DFS3499I ACTIVE DDNAMES: MODBLKSB IMSACBB FORMATB MODSTAT ID: 104
Explanation: Successful COMMIT. ID is incremented and DDNAMES changed. This message is the normal response.
After the response is received from the second part of the successful PREPARE, COMMIT sequence, the command is issued to conclude the PREPARE, COMMIT sequence:
Entry ET:
/MODIFY PREPARE ACBLIB MODBLKS TERMINAL
Response ET:
DFS3499I ACTIVE DDNAMES MODBLKSB IMSACBB FORMATB MODSTAT ID: 104
Explanation: The modifications will be brought online to IMS during a subsequent successful /MODIFY COMMIT command. This message is the normal response.
Entry ET:
/MODIFY COMMIT
Response ET:
DFS3452I WORK IN PROGRESS FOR RESOURCES TO BE CHANGED/DELETED
Explanation: The /MODIFY COMMIT was rejected because changed/deleted resources have not been quiesced.
Entry ET:
/MODIFY ABORT
Response ET:
DFS058I MODIFY ABORT COMMAND COMPLETED
Explanation: Status set by the /MODIFY PREPARE command is reset and the online change does not occur.
This example shows the use of the LTERM keyword when adding, changing, or deleting Fast Path DEDBs or areas.
Entry ET:
/MODIFY PREPARE ALL LTERM WTOR
Response ET:
DFS3499I ACTIVE DDNAMES: MODBLKSA IMSACBA FORMATA MODSTAT ID: 1 DFS3430I THE FOLLOWING MODIFICATIONS WILL OCCUR DURING /MODIFY ... COMMIT: DFS3430I DATABASE CALENDER ADDED DFS3430I DATABASE NEWDD01 ADDED DFS3430I DMB CALENDER ADDED DFS3430I DMB NEWDD01 ADDED DFS3430I DMB DEDBJN23 CHANGED DFS3430I AREA DB23AR4 DELETED DFS3430I AREA DB23AR5 DELETED DFS3430I AREA DB23AR6 DELETED DFS3430I AREA DB23AR7 DELETED DFS3430I DMB DEDBJN24 CHANGED DFS3430I AREA DB24ANU1 ADDED DFS3430I AREA DB24ANU2 ADDED DFS3430I AREA DB24ANU3 ADDED DFS3430I PSB BMP255 CHANGED DFS3430I PSB DDLTFPE4 CHANGED DFS3430I PSB DDLTJN21 CHANGED DFS3430I PSB DDLTRN20 CHANGED DFS3430I TRAN TRAN255 CHANGED DFS3430I TRAN TXCDRN20 CHANGED DFS3430I TRAN TXCD255 CHANGED DFS3430I TRAN TXCD255W CHANGED DFS3430I SECURITY PASSWORD NONE DFS3430I SECURITY TERMINAL NONE DFS3430I SECURITY TRANCMDS NONE DFS3430I SECURITY SIGNON NONE DFS3430I SECURITY AGT NONE DFS3430I END OF MODIFICATIONS
Explanation: The modifications will be brought online to IMS during a subsequent successful /MODIFY COMMIT command. These messages are the normal response.