z/OS V1R6.0 DFSMS Access Method Services for Catalogs

DEFINE CLUSTERRecoverable SphereThe sphere is considered recoverable if LOG(UNDO) or LOG(ALL) isspecified. For a recoverable sphere, VSAM does not allow applications thatdo not support commit and backout to open a data set in the sphere foroutput using RLS access, but applications can open the sphere for outputusing DFSMStvs access. The applications can, however, open the sphere forRLS access for input processing only.If LOG is specified in the SMS data class, the value defined is used as the dataset definition, unless it has been previously defined with an explicitly specifiedor modeled DEFINE attribute.LOG cannot be used with LINEAR.LOGSTREAMID cannot be used with LINEAR.NONEIndicates that neither an external backout nor a forward recovery capabilityis available for the sphere accessed in VSAM RLS or DFSMStvs mode. Ifyou use LOG(NONE), RLS and DFSMStvs consider the sphere to benonrecoverable.UNDOSpecifies that changes to the sphere accessed in VSAM RLS or DFSMStvsmode can be backed out using an external log. RLS and DFSMStvsconsider the sphere to be recoverable when you use LOG(UNDO).ALLSpecifies that changes to the sphere accessed in RLS and DFSMStvs modecan be backed out and forward recovered using external logs. DFSMStvsand RLS consider the sphere recoverable when you use LOG(ALL). Whenyou specify LOG(ALL), you must also specify the LOGSTREAMIDparameter.VSAM RLS and DFSMStvs allow concurrent read or update sharing fornonrecoverable spheres through commit (CICS ® ) and noncommit protocolapplications. For a recoverable sphere, a noncommit protocol applicationmust use DFSMStvs to be able to open the sphere for update using RLSaccess.LOGSTREAMID(logstream)Gives the name of the forward recovery log stream. It applies to allcomponents in the VSAM sphere.If LOGSTREAMID is specified in the SMS data class, the value defined is usedas the data set definition, unless it has been previously defined with anexplicitly specified or modeled DEFINE attribute.logstreamThe name of the forward recovery log stream. This can be a fully qualifiedname up to 26 characters, including separators. If LOG(ALL) is specified,LOGSTREAMID(name) must be specified. For information about defininglog streams for CICS use, see CICS and VSAM Record Level Sharing:Implementation Guide and z/OS DFSMStvs Administration Guide.Abbreviation:LSIDMANAGEMENTCLASS(class)For SMS-managed data sets: Specifies the name, 1-to-8 characters, of themanagement class for a new data set. Your storage administrator defines the158 z/OS V1R6.0 DFSMS Access Method Services for Catalogs