Using Indirect Volume Serials with Cloned zFS Data Sets

Starting with z/OS® V1R12, you can make a clone, or copy, of a zFS and use indirect volume serials to access it. This lets you define a catalog entry for a zFS to specify different volume serials for different systems, which might allow the use of existing processes for cloning systems when zFS is used for the version root file system.

Note:

This support is limited to single volume zFS data sets.
Before attempting the physical copy, make sure the zFS data set is unmounted. If it is not unmounted, it could lead to serialization issues that cause the copy to fail. For more information on the DFSMSdss physical copy operation, refer to DFSMSdss DOC APAR OA39443 or refer to z/OS DFSMSdss Storage Administration.

Do the following steps to clone and catalog a zFS data set with an indirect volume serial:

Clone a zFS by making copies of the existing zFS data sets using COPY with the PHYSINDYNAM (PIDY) parameter for the following reasons:
- Using PHSYINDYNAM creates an uncataloged copy of the data set. Other method create a catalog entry. You need the uncataloged version so that it can be accessed by the catalog entry with the indirect volser.
- Using PHYSINDYNAM (PIDY) lets you use the same name for your original and copied zFS.
The following JCL shows a recommended COPY command to clone a zFS:
```
//STEPT07 EXEC PGM=ADRDSSU
//SYSPRINT DD SYSOUT=*
//SYSIN DD *
COPY DS(INC(ZFS.LDS)) -
PIDY ( -
(1P0301) -
) -
OUTDY ( -
(1P0302) -
) -
REPLACEU -
ALLDATA(*) -
ALLEXCP  
```
See COPY command for DFSMSdss in z/OS DFSMSdss Storage Administrationz/OS DFSMSdss Storage Administration for information about the PHYSINDYAM parameter.
Create a system symbolic in IEASYMxx for &VOL01 for each system that will have a copy of the zFS data set.
See IEASYMxx (symbol definitions) in z/OS MVS Initialization and Tuning Reference.
Enter a DEFINE CLUSTER command with the RECATALOG parameter using the system symbolic (indirect volser) for ZFS.LDS:
```
DEFINE CLUSTER -            
   (NAME(ZFS.LDS) - 
    LINEAR -             
    VOLUMES(&VOL01) -
    RECATALOG)
```
See DEFINE CLUSTER in z/OS DFSMS Access Method Services Commands.
A subsequent IDCAMS LISTCAT command for the LDS will show the following:
```
CLUSTER ------- ZFS.LDS   
...
DATA ------- ZFS.LDS.DATA     
...
VOLUME                                         
  VOLSER------------&VOL01    
DEVTYPE------X'00000000' 
```
Note that the LDS now has a device type of X'00000000'.
See the LISTCAT command in z/OS DFSMS Access Method Services Commands.

Figure 1 provides a visual representation of the zFS Cloning Support Using Indirect VOLSERs.

Figure 1. zFS Cloning Support Using Indirect VOLSERs