The OpenVMS Consultant: OpenVMS Techniques and Knowledge2024-02-28T19:00:00ZRobert Gezelterhttp://www.rlgsc.comtag:www.rlgsc.com,2009-04-01:TheOpenVMSConsultantResource Leaks – Increasing Quotas is not always the solution
I recently answered a query about the
OpenVMS $ASSIGN system service returning SS$_NOIOCHAN (no channel
available). The solution seems obvious: Increase CHANNELCNT. However, in
my experience increasing CHANNELCNT is most often a misleading palliative,
masking the immediate symptom, not an actual solution to the underlying
problem. Increasing CHANNELCNT only delays the inevitable failure. ...
tag:www.rlgsc.com,2024-02-28:resource-leaks-quotas-not-solution2023-02-28T19:00:00Z2023-02-28T19:00:00ZOpenVMS x86-64 Guest Instances and Host Firewalls
Running OpenVMS x86-64 on a virtual machine requires careful
attention to network connectivity between the OpenVMS instance(s)
and the outside network as well as the virtual machine host.
tag:www.rlgsc.com,2023-06-20:openvms-x86-64-guest-instances-and-host-firewalls2023-06-20T08:30:00Z2023-06-20T08:30:00ZForget Looking Back - Clone and Update Forward
Updates are inevitable. With good planning and preparation updates go
smoothly. Without due care, updates can be fraught with challenges.
Some simply install without consequence; others uncover
long-undetected defects in applications and underlying software
layers. ...
tag:www.rlgsc.com,2023-01-09:forget-looking-back-clone-and-update-forward2023-01-09T22:35:00Z2023-01-09T22:35:00ZDCL Command Procedure Parameter Hinting
I write and modify a fair number of DCL command procedures; both for my
own use and as part of my consulting practice. DCL command procedures
allow one to effectively extend the DCL environment beyond what is
provided by baseline OpenVMS. Many, if not most, of these
command procedures have parameters. The parameter(s) may
seem obvious in some cases; in other cases, the parameters are more
complex and/or extensive. ...
tag:www.rlgsc.com,2022-09-06:dcl-procedure-parameter-hinting2022-09-06T13:00:00Z2022-09-06T13:00:00ZOpenVMS 9.2 for x86-64 is now available: Planning a path forward
On July 15th, VMS Software, Inc. (VSI) announced the availability of
OpenVMS 9.2 for Intel x86-64 processors.
The 9.2 release operates under various CPU virtualization products
including VirtualBox, VMware, and KVM. The initial 9.2 release contains
a native MACRO compiler; Itanium-hosted cross compilers are available
for FORTRAN 90, BLISS, COBOL, PASCAL, and C. VSI’s announcement stated
that self-hosted, native compilers will be released as they become
available.[1] Many are considering whether to wait for
the complete suite, or start building experience now. ...
tag:www.rlgsc.com,2022-07-25:OVMS92-release2022-07-25T12:00:00Z2022-07-25T12:00:00Z
Resolving the Contention Problem with ASSIGN/DEFINE
Many sites have processes that modify logical names in shared
logical name tables, e.g., LNM$GROUP, LNM$JOB,
LNM$SYSTEM, and LNM$SYSTEM_DIRECTORY. ...
tag:www.rlgsc.com,2021-02-22:assigncontention2021-02-22T13:15:00Z2021-02-22T13:15:00ZShutdowns using STARTUP.COM
A system can always be shut down by a simply
“hitting the switch” or stopping one or more processes.
The simplicity of such an uncontrolled shutdown is belied by
the effort expended to undo the resulting damage. Orderly shutdowns
create far less damage. ...
tag:www.rlgsc.com,2020-12-28:2020-12-28T12:00:00Z2020-12-28T12:00:00ZAdding a phase to STARTUP
There are nine phases in the base OpenVMS Startup sequence.
Two of these phases are not used. During the other seven phases,
the Startup sequence will execute at least 25 files supplied by
OpenVMS Engineering. ...
tag:www.rlgsc.com,2020-12-21:2020-12-21T12:00:00Z2020-12-21T12:00:00ZAdding a file to STARTUP with SYSMAN
Customizing an OpenVMS configuration is a routine task for both
virtualized and non-virtualized instances. ...
tag:www.rlgsc.com,2020-12-14:2020-12-14T12:00:00Z2020-12-14T12:00:00ZPreparing Applications for OpenVMS x86-64
In a previous installment, I wrote about the general process of preparing
for the integration of OpenVMS x86-64 into general use. While the first
production-ready release of OpenVMS x86-64 is still in the future, there
are many steps which can be taken now. This preparation will make the
arrival of OpenVMS x86-64 Version 9.2 far easier when the time comes. ...
tag:www.rlgsc.com,2020-06-22:2020-06-22T12:00:00Z2020-06-22T12:00:00ZPlanning for OpenVMS x86-64
It has been five years since VMS Software, Inc. (VSI) announced that
it was in the process of porting OpenVMS to Intel's x86-64 processors.
The fruits of this effort will be soon available. Initially there will
be an Early Adopters Kit (EAK) referred to as Version 9.1. The
production-quality release will be Version 9.2. Now is the appropriate
time for ISVs, OEMs, and end-users to give thought to the process of
porting and qualifying their software and applications on
OpenVMSx86-64. ...
tag:www.rlgsc.com,2020-01-30:2020-01-30T12:00:00Z2020-01-30T12:00:00ZDigital Forensics and E-Discovery on OpenVMS
Litigation and legal processes are increasingly part of the general IT
landscape. Digital forensics and electronic discovery (often referred to as
“e-discovery”) have become inescapable facts of business life.
OpenVMS system managers
need to proactively develop the plans, processes, and procedures needed to
respond to these inevitable legal process requests. Correctly dealing with
these requests minimizes the impact on production systems. Failure to
address these situations correctly can expose the organization to significant
liability.
tag:www.rlgsc.com,2011-02-21:digital-forensics-and-ediscovery-openvms2011-02-21T10:56:00Z2011-02-21T10:56:00ZDCL File Access
Creating, reading, and writing files are common programming tasks,
particularly with DCL and other scripting languages. While syntax
and semantics for file operations vary between various languages,
few of these differences are consequential; most are merely
questions of syntax. Discerning which differences are significant
from the insignificant differences in syntax often has subtleties.
In the case of OpenVMS DCL, the precise syntax for the OPEN command
can give rise to misleading presumptions. These syntactic
presumptions sometimes produce confusion, particularly when viewed
from the perspective of programming in other environments. This
need not be the case. DCL's file handling is as powerful as most
any third generation programming language, once the syntax and
its implications are understood. ...
tag:www.rlgsc.com,2011-02-06:DCL-File-Access2011-02-07T04:56:00Z2011-02-07T04:56:00ZDCL Call Forward and Callback
It is the rare DCL command procedure that is an island unto itself. Rather,
it is far more common for DCL procedures to be parts of larger ensembles;
collections of pre-existing and purpose-developed tools working in concert
to achieve a common purpose. Calls to lower-level DCL procedures and
callbacks to user-provided processing are integral to assembling these
ensembles which by their very nature leverage development and
maintenance resources. ...
tag:www.rlgsc.com,2010-12-30:DCL-Call-Forward-and-Callback2010-12-31T00:51:00Z2010-12-31T00:51:00ZClimbing the Spiral: A Better Rightsizing Paradigm
The first question discussed when planning a new system is often:
“How large a system should be purchased.” Many times,
system sizing is done long before anyone has any sound estimates
of system utilization of load. Decisions on sizing are often made
long before the relevant code is even designed, much
less written and debugged. ...
tag:www.rlgsc.com,2010-11-18:climbing-the-spiral2010-11-23T14:43:00Z2010-11-23T14:43:43ZFilename Alchemy - F$PARSE Defaulting
Pervasive uniform file typing is a well-known feature of OpenVMS. In fact, it is a design choice
passed to OpenVMS from its antecedents. Source files for each language have a distinct file type
(e.g., .FOR, .C, .CXX, .COB, .PAS, .PLI, .MAR, .BAS). Other files, produced from these source
files have their own distinctive file types, .EXE, .LIS, .EXE, .STB, .MAP, to name but a few
of the standardized possibilities. Implementing these naming conventions is often incorrectly
seen as an unwieldy chore; nothing could be further from the truth. The OpenVMS SYS$PARSE
system service, and the corresponding DCL lexical function, F$PARSE provide all that is
needed for implementation in a single call. ...
tag:www.rlgsc.com,2010-10-19:Filename-Alchemy-F$PARSE-Defaulting2010-10-19T09:27:00Z2010-10-19T09:27:00ZGroup-wide LOGIN Profiles Lower Risk, Decrease Cost
Making changes to SYS$MANAGER:SYLOGIN.COM is potentially hazardous. What
seems like an insignificant change can have regrettable side effects. In some cases,
a change made to enhance the interactive environment has caused production batch and
detached processes to fail. In other cases, different parts of a user community find
themselves at odds over a particular change. These difficulties are unnecessary. Enhancing
SYS$MANAGER:SYLOGIN.COM to support group-specific login processing is
straightforward, decreases risks of collateral damage, and simplifies system management
workload. ...
tag:www.rlgsc.com,2010-09-30:group-wide-login-profiles-lower-risk-decrease-cost2010-09-30T16:00:00Z2010-09-30T16:00:00ZSYS$MANAGER:SYLOGIN.COM - Verification of SYLOGIN Processing Without Disruption
OpenVMS LOGINOUT and CLI initialization provide a powerful tool for
customizing individual OpenVMS sessions. However, this power is not without hazard.
Errors in customization can easily lead to inappropriate process contexts, which can lead
to software failures and disruptions of system availability. Establishing a framework for
fault isolation and diagnosis greatly reduces these risks. ...
tag:www.rlgsc.com,2010-07-12:SYS$MANAGER%3ASYLOGIN.COM-Verification2010-07-12T23:43:00Z2010-07-12T23:43:00ZSYS$MANAGER:SYLOGIN.COM - Flexibility Requires Prudence
Processes are a foundational OpenVMS unit. Process creation is the
common origin for all OpenVMS activity, whether an interactive session,
batch job, network server, or detached proccess. While a process can be
created without a CLI context, it is more common to create a process with
a CLI context. In most cases, the CLI is the OpenVMS standard: DCL. ...
tag:www.rlgsc.com,2010-04-26:SYS$MANAGER-SYLOGIN.COM2010-04-26T14:00:00Z2010-04-26T14:00:00ZSingle Command Batch Jobs: An Alternative to SPAWN or Command Files
Small command files clutter far too many directories. It is a tendency I see both within
my own project directories and in those belonging to colleagues and clients. This
plethora of command files implements a variety of tasks. Some tasks require logging;
other tasks are too long in duration to run interactively. This begs the question: How
can normal OpenVMS facilities eliminate the need for these files? ...
tag:www.rlgsc.com,2010-03-11:Single-Command-Batch-Jobs2010-03-12T20:15:00Z2010-03-12T20:15:00ZSoloist OpenVMS Clusters: A New Perspective to Improve Functionality, Flexibility, and Usability
Standalone OpenVMS systems and OpenVMS clusters are generally thought of as distinct configuration
alternatives. This distinction has long outlived its usefulness and should be removed. In its place, I propose
Soloist OpenVMS Cluster as a more appropriate nomenclature and useful default configuration.
A Soloist OpenVMS Cluster is an OpenVMS Cluster containing a single system. This posture
should be the preferred configuration for single OpenVMS systems. Such an OpenVMS Cluster may be a
rivial instance of an OpenVMS Cluster, but it has significant advantages when viewed from a long-term
perspective. This change in posture allows seamless transition of operations to a multi-node OpenVMS
Cluster at some future time, on either a temporary or permanent basis. ...
tag:www.rlgsc.com,2010-01-13:Soloist-OpenVMS2010-01-13T04:57:00Z2010-01-13T04:57:00ZWhy OpenVMS?
I have been asked: "Why choose OpenVMS?". It is a question worth asking. ...
tag:www.rlgsc.com,2009-11-03:Why-OpenVMS2009-11-03T15:22:00Z2009-11-03T15:22:00ZDCL Computed GOTO
Multiple choice transfers of control are one of the most time-honored
facilities in programming languages, be they conventional or scripting,
interpreted or compiled, assembler or very high level. It is often
mistakenly believed that indirection is needed for implementation,
but this is not the case. Perfectly serviceable multi-way branches
can be implemented without indirection. All that is necessary is
some method of re-computing the location of the next instruction
(or line in a scripting language) to be executed.
tag:www.rlgsc.com,2009-06-09:DCL-Computed-GOTO2009-06-09T20:43:57Z2009-06-09T20:43:57ZDCL Symbols: Starting at the beginning
Those unfamiliar with OpenVMS DCL symbol substitution often find it a source of confusion.
This powerful DCL feature is avoided out of misunderstanding. This is very unfortunate,
since symbol substitution dramatically shortens development tasks and reduces the cost of ongoing maintenance.
tag:www.rlgsc.com,2009-03-02:DCL-Symbols-Starting-at-the-beginning2009-03-02T10:00:00Z2009-03-02T10:00:00ZOpenVMS DEBUG: Often underutilized and unappreciated
This column is the first in a series of columns about the capabilities and use of the
OpenVMS debugger, DEBUG. The OpenVMS Documentation set includes an extensive treatment
of DEBUG in the “HP OpenVMS Debugger Manual”. The manual is available on the OpenVMS
www site in both HTML and PDF versions.
DEBUG is one of the fundamental software development tools on OpenVMS.
At its most elemental, DEBUG allows a programmer to interrupt program execution
at pre-selected points in the source program, display and possibly alter
variables, and continue execution.
tag:www.rlgsc.com,2009-02-03:OpenVMS-DEBUG-Often-underutilized-and-unappreciated2009-02-03T10:00:00Z2009-02-03T10:00:00Zftp and sneakernet Are Not Your Only Options
Transferring files from one system to another is a routine operation. In some cases, the
transfer is a one-shot, a single one-time operation, for example the migration to a new
system. In other cases, the transfer is part of an ongoing process, and will be done
repeatedly. I have had clients where file transfers were part of daily or hourly
operational procedures.
tag:www.rlgsc.com,2005-07-09:ftp-and-sneakernet-are-not-your-only-options2005-07-09T10:00:00Z2005-07-09T10:00:00ZVanquishing the Smoke and Fog with Facts
Recent announcements by HP and Intel concerning the re-arrangement of the development team
for the Itanium series of microprocessors have prompted much discussion and a fair bit of
concern in our community.
Suggestions that Intel is "helping HP abandon Itanium by buying the development team" are
simply not consistent with the facts.
tag:www.rlgsc.com,2004-12-17:vanquishing-the-smoke-and-fog-with-facts2004-12-17T10:00:00Z2004-12-17T10:00:00ZOpenVMS HP-Intel Developer Forum - Report from the Front Lines
I just returned from spending three days with the OpenVMS stream of the HP - Intel Developer
Forum in Mahwah, New Jersey. The over-subscribed OpenVMS stream was extremely successful,
and provided an advanced view of what OpenVMS users can expect from the soon-to-be
generally released OpenVMS for HP Integrity Servers.
tag:www.rlgsc.com,2004-12-07:OpenVMS-HP-Intel-Developer-Forum-report-from-the-front-lines2004-12-07T10:00:00Z2004-12-07T10:00:00ZHPWORLD 2004 -- Noteworthy OpenVMS Technical News
Recently returned from HPWORLD 2004 in Chicago, I can report that there is interesting news
in the OpenVMS arena. On the technical front, much of the news was expected, with OpenVMS 8.2
for both Alpha and Itanium having entered field test at the end of July, as projected.
OpenVMS VAX 8.2 will be a few months later in the cycle, due to scheduling reasons.
tag:www.rlgsc.com,2004-09-05:HPWORLD-2004-Noteworthy-OpenVMS-Technical-News2004-09-05T10:00:00Z2004-09-05T10:00:00ZServer Consolidation: Back to the Future
Computing is as subject to fashions and fads as any other human activity. Trendy ideas
are fashions of the moment, and soon fall out of favor. Good ideas may temporarily fall
from favor and seem unfashionable; yet in the end are timeless. So it is far from surprising
that today's computing milieu has come full circle, and multi-role servers are once again
the rage; with major manufacturers and research firms promoting the Total Cost of Ownership
(TCO) benefits of server consolidation. Yet these very same manufacturers and research
firms often had, just a short time previously, declared multi-role central (or organizational)
systems “dead”; declaring instead that the wave of the future was the unconstrained
proliferation of small systems liberated from the burden of central control. At that
time, it was argued that freedom from central control was beneficial.
tag:www.rlgsc.com,2003-08-06:Server-Consolidation-Back-to-the-Future2003-08-06T10:00:00Z2003-08-06T10:00:00ZPitfalls of F$LOCATE and other Functions
Code that is almost correct is pernicious, and I often encounter it in the course of my
consulting practice. While working on a client problem the other day, I encountered just
such an example, an almost correct use of F$LOCATE to determine if a process holds a
particular privilege or identifier. The fault is not in F$LOCATE, it is in the way
that F$LOCATE (or any other index function) is used.
tag:www.rlgsc.com,2003-03-31:Pitfalls-of-F$LOCATE-and-other-Functions2003-03-31T10:00:00Z2003-03-31T10:00:00ZLogical Names -- Part 5
In a prior installment, I promised a slightly more sophisticated example using logical
names. A straightforward, yet extraordinarily common situation presents a logical first
example: DISK$USERS (or as I often encounter it, DISK$department, where department can
be anything from ACCOUNTING to ZOOLOGY).
tag:www.rlgsc.com,2003-03-03:Logical-Names-Part-52003-03-03T10:00:00Z2003-03-03T10:00:00ZLogical Names -- Part 4
There is one additional set of qualifiers on the ASSIGN command which are often used,
and we will encounter when constructing examples. These parameters affect the mode
of the logical name created/redefined by the $CRELNM system service used by the
implementation of the ASSIGN command
tag:www.rlgsc.com,2003-02-06:Logical-Names-Part-42003-02-06T10:00:00Z2003-02-06T10:00:00ZReport from the 1st OpenVMS Technical Symposium -- Part 1
I have just returned from the OpenVMS Technical Seminar hosted by OpenVMS Engineering
in Nashua, New Hampshire on November 19-21. The three days of sessions extensively
covered topics including the assimilation of Itanium CPUs, hands-on training for
Next Generation Alpha-based systems, E-Commerce, Probably, the hottest issue in
the OpenVMS community is support for Intel's Itanium processor. The presentations
on the Itanium effort were made by senior engineers from the OpenVMS team,
including Andrew Goldstein, Clair Grant, Stephen Hoffman, and Gaitan D'Antoni.
tag:www.rlgsc.com,2002-12-04:Report-from-the-1st-OpenVMS-Technical-Symposium2002-12-04T10:00:00Z2002-12-04T10:00:00ZLogical Names -- Part 3
Originally, I intended to devote this installment to a more detailed discussion
of a typical, everyday use of logical names. In developing the example, I
realized that we need first review some of the options on the ASSIGN command
(the syntax of the DEFINE command is similar, although the operands are
reversed); most people prefer one or the other for admittedly ideosyncratic
reasons. Going through the different qualifiers and their effects will occupy
more than a single column, so we will defer the example (which uses multiple
qualifiers) by two columns, to Part 5.
tag:www.rlgsc.com,2002-11-04:Logical-Names-Part-32002-11-04T10:00:00Z2002-11-04T10:00:00ZLogical Names -- Part 2
The previous column (Part 1) examined the basics of the OpenVMS logical name
facility. This installment focusses on how applications use and misuse logical names.
tag:www.rlgsc.com,2002-10-17:Logical-Names-Part-22002-10-17T10:00:00Z2002-10-17T10:00:00ZLogical Names -- Part 1
OpenVMS is, somewhat unique among operating systems for the operational flexibility
it offers. It is not unusual for even system managers to go for years without needing
to pay attention to which physical drive an application is using. One of these
distinguishing features is the Logical Name facility, a vital, yet often
under-appreciated guarantor of flexibility.
tag:www.rlgsc.com,2002-09-24:Logical-Names-Part-12002-09-24T10:00:00Z2002-09-24T10:00:00Z