VSAM files accessed in RLS mode
If you specify file definitions that open a data set in RLS mode, you must 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 attributes in the ICF catalog enforces the same attributes, for all CICS regions in the sysplex, for all the files opened against a given sphere.
- LOG({NONE | UNDO| ALL})
- 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. Use LOG(ALL) for files that you want to recover using CICS VR. 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 MVS 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 an MVS log stream name when it attempts to open a data set in RLS mode. The open fails if the log stream is not defined and cannot be created dynamically.
- BWO(TYPECICS | TYPEIMS | TYPEOTHER | NO)
- TYPECICS specifies that CICS BWO support is required. This is the equivalent of BACKUPTYPE(DYNAMIC) in the CSD. The other values refer to non-CICS support.
If you omit the LOG parameter when you define 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 these ICF parameters, see z/OS® DFSMS Access Method Services.