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DFSMS Elements

The z/OS operating system enables you to efficiently manage e-business workloads and enterprise transactions 24 hours a day. Data Facility Storage Management Subsystem (DFSMS) comprises a suite of related data and storage management products for the z/OS system, helping to automate and centralize the management of storage based on the policies that your installation defines for availability, performance, space, and security. The heart of DFSMS is the Storage Management Subsystem (SMS). Using SMS, the storage administrator defines policies that automate the management of storage and hardware devices. These policies describe data allocation characteristics, performance and availability goals, backup and retention requirements, and storage requirements for the system and reduce the need for users to make many detailed decisions that are not related to their business objectives.

DFSMSdfp is automatically included with z/OS. The combined components of DFSMSdfp provide the essential data, storage, and device management functions of the system, along with Advanced Copy Services functions for disaster recovery and high availability.

DFSMSdss, DFSMShsm, DFSMSrmm, DFSMStvs, and DFSORT complement DFSMSdfp to provide a fully-integrated approach to data and storage management. In a system-managed storage environment, the full DFSMS suite automates and centralizes storage management based on the policies that your installation defines for availability, performance, space, and security. With these optional features enabled, you can take full advantage of all the functions that DFSMS offers.

DFSMS Mission Statement

The Data

Deliver structured and unstructured data through modernization and enhancements in storing, accessing, managing, auditing and protecting the data allowing clients to scale with performance.

Cyber Resiliency

Deliver regulatory, service level agreements, and business operational requirements for cyber resiliency for data protection and recovery (high availability, disaster recovery, backup, and continuous protection).

Data Lifecycle

Deliver seamlessly integrated online and offline storage tiers (including cloud) driven by serverless data movement.

Elements of DFSMS

DFSMS is an exclusive element of the z/OS® operating system. DFSMS is a software suite that automatically manages data from creation to expiration. The following elements comprise DFSMS:

Provides I/O to storage devices through a number of protocols (access methods). Manages the data residing on storage devices. Provides control and reporting interfaces (ISMF) to end users and system administrators.
Data Set Services (DSS)
Provides backup/recovery, data movement/replication and space management services.
Hierarchical Storage Manager (HSM)
Provides policy driven backup/recovery, hierarchical storage management and disk space management for structured data.
RMM (Tape Management)
Manages through policies (tape volumes, tape data sets, and tape libraries).
Transactional Virtual Access Method Services (TVS)
Enables batch processing of VSAM data sets concurrently with CICS online processing.
Provides sorting, merging, copying, and reporting of records within files.


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