VSAM record-level sharing (RLS) enables data sharing across multiple systems in a Parallel Sysplex®. VSAM RLS is a data set access mode that allows CICS®, batch, and non-CICS applications that run in multiple address spaces and on multiple z/OS systems to access data at the same time. VSAM RLS is designed for online transaction processing (OLTP) with CICS Transaction Server and applications that use VSAM data sets.

With VSAM RLS, multiple CICS systems can directly access a shared VSAM data set. CICS provides the logging, commit, and rollback functions for VSAM recoverable files. VSAM uses the coupling facility (CF) to provide record-level serialization and cross-system caching. IBM® CICS VSAM Recovery (CICSVR) recovers lost or damaged VSAM data sets.

CICSVR is for organizations where the availability and integrity of VSAM data is vital. CICSVR provides automated complete recovery, forward recovery, and backout functions, as well as logging for batch applications.

You can use VSAM RLS with DFSMStvs to run concurrent batch VSAM jobs and CICS online transactions against the same recoverable VSAM data set. DFSMStvs also provides forward recovery logging for recoverable data sets. If data is lost or damaged, you can restore it from a backup and use CICSVR to reapply the changes that were made since the last backup.