VSAM files accessed in RLS mode

If you specify file definitions that open a data set in RLS mode, specify the recovery options in the ICF catalog.

The recovery options on the CICS file resource definitions (RECOVERY, FWDRECOVLOG, and BACKUPTYPE) are ignored if the file definition specifies RLS access.

The VSAM parameters LOG and LOGSTREAMID, on the access methods services DEFINE CLUSTER and ALTER commands, determine recoverability for the entire sphere. Locating these recovery parameters in the ICF catalog enforces the same options, for all CICS regions in the sysplex, for all the files opened against a given sphere.

LOG({NONEUNDOALL})

Specifies the type of recovery required for the VSAM sphere. Specify the LOG parameter for data sets that are to be used by CICS in RLS mode.

NONE

The sphere is not recoverable.

UNDO

The sphere is recoverable. CICS must maintain system log records for backout purposes.

ALL

The sphere is recoverable for both backout and forward recovery. CICS must maintain system log records (as for UNDO) and forward recovery log records. If you specify LOG(ALL), also specify LOGSTREAMID to indicate the name of the forward recovery log.

Note: Forward recovery support is available for recoverable files only—you cannot have forward recovery without backout recovery.

LOGSTREAMID(log_stream_name)

Specifies the name of the log stream to be used for forward recovery log records when LOG(ALL) is defined. Note that IDCAMS does not check for the presence of the LOGSTREAMID during DEFINE processing. CICS checks for a log stream name when attempting to open a data set defined with LOG(ALL), and the open fails if the log stream is not defined and cannot be created dynamically.

If you omit the LOG parameter when defining your VSAM data sets, recovery is assumed to be UNDEFINED, and the data set cannot be opened in RLS mode. You can also set the UNDEFINED status explicitly by specifying NULLIFY(LOG).

For information about the access methods services DEFINE and ALTER commands, see z/OS DFSMS: Access Method Services for ICF and z/OS DFSMS: Using data sets.

Inquiring on recovery attributes:

You can use CEMT, or EXEC CICS, INQUIRE FILE and INQUIRE DSNAME commands to determine the recovery options that are specified for files and data sets.

The INQUIRE FILE command shows the options from the CICS file definition until the first file for the data set is opened. If the options are obtained from the ICF catalog when the first file is opened, the ICF catalog values are returned. The

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IBM SC34-7012-01 manual Vsam files accessed in RLS mode, Inquiring on recovery attributes