Global Shutdown Processing
CA MIM for z/OSperforms several actions to ensure the integrity of your resources at termination. When you stop CA MIM on all systems in your complex, components and facilities take the following actions:
Using Global SHUTDOWN Commands to Stop CA MIM for z/OS
WARNING!Stopping CA MIM when GTAF or GDIF is running may create data integrity exposures.
We strongly recommend that you use caution if attempting to shut down a subset of the systems in the MIMplex. If you are not confident that you can safely avoid data integrity exposures, contact CA Technical Support for assistance.
To stop CA MIM on all systems rather than on a subset of the systems in your complex, issue a z/OS STOP or the CA MIM SHUTDOWN command. To use the z/OS STOP command, specify the name of the CA MIM started task as a parameter. For example, if MIMGR is the name of the started task that you want to stop, then issue this shortened form of the z/OS STOP command:
CA MIM then issues message MIM0060, which asks what type of processing you want to perform at termination. Reply GLOBAL to stop on all systems and to have CA MIM terminate on all systems.
You can also use the SHUTDOWN GLOBAL command to stop CA MIM on all systems. For example, if MIMGR is the name of the started task that you want to stop then issue this SHUTDOWN command from any system:
F MIMGR,SHUTDOWN GLOBAL
GLOBAL is the initial default value of the command. You can change the default value of the command to DUMP, FREE, LOCAL, or RESERVE with the SETOPTION SHUTDOWN command.
For a description of the SHUTDOWN command, see the
Statement and Command Reference Guide.
When GLOBAL is selected, CA MIM for z/OS does not stop with an abend code or request an abend dump.
CA MIA Activities During Global Shutdown
The following actions are taken by CA MIA in response to a MIM SHUTDOWN,GLOBAL command request:
- GTAF takes offline all unallocated devices on each system. This prevents z/OS from selecting these devices.
- GTAF marks all allocated devices on the system to which they are allocated as PENDING OFFLINE. This causes the local z/OS operating system to take the devices offline as soon as they are deallocated. GTAF takes the devices offline on all other systems.
- TPCF restores control to z/OS for any job that is in the allocation recovery process. TPCF replies with an invalid response to any outstanding z/OS IEF238D message, which restores control to z/OS and causes z/OS to prompt you for information.
CA recognizes that it may not be possible to quiesce all tape activity on a system. It is possible to safely stop CA MIM for z/OS on one local system without quiescing all tape activity. However, it is not practical to document every situation that may occur under such circumstances.
NOTE: When CA MIA is not running, the operator may share tape devices manually by using z/OS VARY OFFLINE and VARY ONLINE commands. To maintain device integrity, you must ensure that each device is online to only one system at a time.
CA MIC Activities During Global Shutdown
The following actions are taken by CA MIC in response to a MIM SHUTDOWN,GLOBAL command request:
- GCMF terminates any incomplete multiple-line messages.
- GCMF deletes all highlighted messages from other systems.
- GCMF deallocates or deactivates subsystems or extended consoles used.
- ICMF notifies CA-L-Serv that it is terminating.
CA MII Activities During Global Shutdown
The following actions are taken by CA MII in response to a MIM SHUTDOWN,GLOBAL command request:
- GDIF stops propagating new ENQ and RESERVE requests.
- GDIF stops eliminating hardware reserves for any new RESERVE requests.
- GDIF does not restore any of the hardware reserves that it has converted.
- GDIF continues to perform quiesce processing for any outstanding RESERVE requests that it already has converted and any requests included in a global conflict.
- The ECMF REQUEUE feature handles requeued jobs and checkpoint information you have specified through the REQCKPT parameter on a SETOPTION command.
How You Automatically Free a System From the MIMplex
The auto FREE feature provides a means to automate the FREE command operation for a CA MIM member on a failed system in a sysplex. The auto FREE feature functions independently of the MIMplex control file communication methodology.
The auto FREE feature works by reacting to a notification event provided by the XCF/XES operating system component, which describes that a system has been removed from the active sysplex.
For information on sysplex member removal, see the IBM MVS guide
Setting Up a Sysplex.
The MIMplex can be a subset of a sysplex, or it can be comprised of more than one sysplex. As long as one member of a sysplex survives to provide a system down notification event, the auto FREE feature automatically FREEs the removed MIMplex member. A MIMplex member must be a member of a sysplex to be automatically freed with auto FREE. The system down notification event is provided by the XCF/XES operating system component, in a sysplex environment.
In addition to the MIMplex configuration relationship to the sysplex configuration, consider the following regarding the use of the auto FREE feature:
- The auto FREE feature is controlled by the SETOPTION MIM DOWNSYS command and can be enabled or disabled on an individual system basis in the MIMplex. DOWNSYS=AUTOFREE needs to be specified on the surviving sysplex member to react to the incoming system down event.
To relate CA MIM for z/OS system names with z/OS system names, the z/OS system name, rather than the z/OS SMF ID, must be specified on the DEFSYS statement. The z/OS system name is defined on the SYSNAME keyword of the IEASYSnn member of the z/OS SYS1.PARMLIB data set. The z/OS DISPLAY XCF,SYSPLEX,ALL command can be used to list all of the z/OS system names in a given sysplex. Alternately, the z/OS DISPLAY SYMBOLS command shows the local z/OS system name for the &SYSNAME variable name.