HP OpenVMS I64 Operating Systems Disk and Tape Volumes, Business and Integration Technologies

Models: OpenVMS I64 Operating Systems

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HP OpenVMS Alpha Version 8.3 and HP OpenVMS Version 8.3-1H1 for Integrity Servers SPD 82.35.13

Record Management Services (RMS)

RMS is a set of I/O services that helps application pro- grams to process and manage files and records. Al- though it is intended to provide a comprehensive soft- ware interface to mass storage devices, RMS also sup- ports device-independent access to unit-record devices.

RMS supports sequential, relative, and indexed file or- ganizations in fixed-length or variable-length record for- mats. RMS also supports byte stream formats for se- quential file organization.

RMS record access modes provide access to records in four ways:

Sequentially

Directly by key value

Directly by relative record number

Directly by record file address

RMS also supports block I/O operations for vari- ous performance-critical applications that require user- defined file organizations and record formats.

RMS promotes safe and efficient file sharing by pro- viding multiple file access modes and automatic record locking (where applicable). RMS offers the options of enabling global buffers for buffer sharing by multiple pro- cesses.

RMS utilities aid file creation and record maintenance. These utilities convert files from one organization and format to another; restructure indexed files for storage and access efficiency; and reclaim data structures within indexed files. These utilities also generate appropriate reports.

For systems that have DECnet or DECnet-Plus in- stalled, RMS provides a subset of file and record man- agement services to remote network nodes. Remote file operations are generally transparent to user programs.

Commands such as EDIT, CREATE, COPY, TYPE, and PRINT allow users to manipulate RMS records within RMS files at the DCL command level.

Disk and Tape Volumes

The system manager can organize disk volumes into volume sets. Volume sets can contain a mix of disk device types and can be extended by adding volumes. Within a volume set, files of any organization type can span multiple volumes. Files can be allocated to the set as a whole (the default) or to specific volumes within the set. Optionally, the system manager can allocate portions of indexed files to specific areas of a single disk or to specific volumes in a volume set.

The system manager can place quotas on a disk to con- trol the amount of space individual users can allocate. Quota assignment is made by UIC and can be controlled for each individual volume set in the system (or for each individual volume if the volume is not part of a set).

The system manager can cache disk structure infor- mation in memory to reduce the I/O overhead required for file management services. Although not required to do so, users can preallocate space and control auto- matic allocation. For example, a file can be extended by a given number of blocks, contiguously or noncon- tiguously, for optimal file system performance.

The system applies software validity checks and check- sums to critical disk structure information. If a disk is improperly dismounted because of user error or system failure, the system rebuilds the disk’s structure informa- tion automatically the next time the disk is mounted. The system detects bad blocks and prevents their reuse once the files to which the blocks were allocated are deleted. On DIGITAL Storage Architecture (DSA) disks, the disk controller detects and replaces bad blocks au- tomatically.

The system provides 255 levels of named directories and subdirectories whose contents are alphabetically or- dered. Device and file specifications follow HP conven- tions. Users can use logical names to abbreviate the specifications and to make application programs device and file name independent. Users can assign a logical name to an entire specification, to a portion of a speci- fication, or to another logical name.

OpenVMS supports multivolume magnetic tape files with transparent volume switching. Access positioning is done either by file name or by relative file position.

E-BUSINESS AND INTEGRATION TECHNOLOGIES

The HP OpenVMS e-Business and Integration Infras- tructure Package provides key Internet, e-business, and integration software technologies that enhance the OpenVMS Alpha and OpenVMS for Integrity servers operating systems and enable the development of e- business and enterprise integration solutions. These technologies are bundled with the OpenVMS Alpha or OpenVMS for Integrity servers operating systems. Sev- eral of the components are additionally bound by an open source software license.

The following components are included on the e- Business and Integration Infrastructure Package on OpenVMS Alpha:

HP Secure Web Server (SWS), including support for the popular scripting capabilities: mod_PHP, mod_ Perl and Perl, and JavaServer Pages (Tomcat)

HP Secure Web Browser (SWB)

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HP OpenVMS I64 Operating Systems manual Disk and Tape Volumes, Business and Integration Technologies