HSMS (Hierarchical Storage Management System) is a BS2000 software product for data backup which supports data management on external storage devices in a BS2000 system. HSMS also supports Net-Storage connected via NFS with the Net-Storage files cataloged in BS2000. Net-Storage serves to expand local pubsets and collaboration with open world systems. For more details refer to the manual “Introductory Guide to DMS” [4]. Since HSMS V12.0C Net-Storage files residing on NETVOL volumes and cataloged in BS2000 are supported. Unless otherwise specified explicitly, the term "Net-Storage" refers to both volume types NETSTOR and NETVOL within the whole manual.
In HSMS V10.0 and higher, a BS2000 backup server can be configured in the shared pubset network which handles the backup tasks for all other BS2000 hosts in this network. This relieves the load on the productive systems.
HSMS also enables data of networked, remote UNIX systems, network servers or workstations to be saved and, when required, restored. To permit this, these systems must be connected to the local BS2000-UFS (POSIX) via NFS.
Computer centers have to process ever increasing quantities of data. The amount of personnel and volumes required for creating and managing backup copies of the data processed has grown accordingly.
HSMS provides computer center and database administrators with a backup function which permits both incremental and partial backup as well as the continuation of backup volumes, and thus helps to save time and space.
In many cases, old data inventories in a system are required only in exceptional cases. Nevertheless they have to be kept on a long-term basis, either to comply with legal regulations or to provide against disaster. To this end, HSMS offers an archival (long-term data saving) function that is independent of the backup function. The data saved by the archival function is managed in separate archives independently of the data saved by the backup function.
The demand for online disk storages in particular has increased enormously. This results in considerable costs for devices, floor space and management. On the other hand, as a safeguard against saturation, many disk storages are not used to capacity. The migration function offered by HSMS is a mechanism designed to make better use of disk storage capacity: during operation, data that has not been used for some time is moved from the processing level to the background level. Migration can also be started automatically when saturation levels are reached.
The data can be recalled to the processing level as required even without the user calling HSMS.
HSMS implements the basic functions of backup, archival and migration in a three-level hierarchy of external storages. The volumes of a BS2000 system – disk storages and magnetic tape cartridges – are assigned to the various hierarchical levels depending on their performance characteristics with regard to storage costs and access time requirements. The normal processing level is assigned an online background level consisting of disk storages and an offline background level consisting of magnetic tape cartridges.
In addition to the single feature pubsets (SF pubsets), HSMS supports the system-managed pubsets (SM pubsets) in a special manner as the background and storage levels with the puset's metainformation are integrated into thiese and backup and migration strategies can be controlled by means of management classes.
With its data transfer function, moreover, HSMS provides the option of transferring files, job variables and even catalog entries of BS2000 files to other BS2000 systems or other user IDs, using magnetic tape cartridges. Data transfer is equivalent to the
EXPORT/IMPORT function of ARCHIVE; as a result, volumes created with either HSMS or ARCHIVE are interchangeable.
HSMS includes the software product ARCHIVE. In addition, HSMS optionally interoperates with the software products MAREN and ROBAR.
For BS2000 files, a smooth changeover from ARCHIVE to HSMS is ensured by the compatibility of the archive directory files and backup volumes of the two products.
HSMS is operated via an easy-to-use user interface. HSMS statements are entered via SDF.
HSMS offers a variety of control and inquiry functions, such as:
restricting tape processing to specially reserved times
restarting interrupted requests
obtaining information about the occupancy and utilization of public volume sets.
The files to be processed by the basic functions are determined by means of user-friendly selection mechanisms.