IBM SC34-7012-01 - Manual (Page 216)

forward-recovery logs. Long-running transactions, automated teller machines, and
continuously available applications require the database to be up and running
when the backup is being taken.
The concurrent copy function used along with BWO by DFSMSdss allows backups
to be taken with integrity even when control-area and control-interval splits and
data set additions (new extents or add-to-end) are occurring for VSAM key
sequenced data sets.
BWO requirements
To use the backup-while-open (BWO) support provided by CICS, you can use the
Data Facility Storage Management Subsystem/MVS (DFSMS/MVS) or a program
product that provides equivalent function.
You must have your environment configured with the following modules and
components:
v Use Release 2, or later, for data sets used in non-RLS access mode and Release 3
for data sets used in RLS access mode.
v You must install the DFSMSdfp IGWAMCS2 callable services module in the link
pack area (LPA).
v You must install the IGWABWO module, supplied in SYS1.CSSLIB, in the LPA,
or include SYS1.CSSLIB in the link list. Do not include the library in the
STEPLIB or JOBLIB library concatenations.
v You must have the DFSMSdfp, DFSMSdss, and DFSMShsm components of
DFSMS installed on the processors that perform backup and recovery.
During initialization, CICS determines the availability of BWO support by issuing
calls to the callable services modules IGWAMCS2 and IGWABWO. CICS also
checks on the DFSMSdss release level by calling the DFSMSdss module
ADRRELVL. If access to this DFSMSdss module is strictly controlled by an external
security manager, such as RACF, security violation messages are issued against the
CICS userid, unless the CICS region userid is authorized to access this module.
Note that CICS VSAM Recovery for z/OS, which performs forward recovery, must
be installed on the processor where forward recovery is to be done. CICS VSAM
Recovery is required for forward recovery and backout of CICS VSAM data sets
backed up with BWO and concurrent copy functions of DFSMS/MVS.
Table 2 cross-references the storage management component names of DFSMS to
the previous names of the individual licensed programs:
Table 2. Cross-reference of DFSMS/MVS product terminology
Component name Full DFSMS/MVS name Previous product
name
DFSMSdfp Data Facility Storage Management
Subsystem data facility product MVS/DFP
DFSMShsm Data Facility Storage Management
Subsystem hierarchical storage manager DFHSM
DFSMSdss Data Facility Storage Management
Subsystem data set services DFDSS
204 CICS TS for z/OS 4.1: Recovery and Restart Guide