OpenVMS Mini FAQ
(From real questions I get all the time)
Overview: In mid 2005, I spent a week at
Learning Tree in Toronto which
meant I got a chance to mingle with computer professionals outside of
the OpenVMS world. Most people I met were either "UNIX acolytes" or
"Windows wonks". About 90% knew about VAX, VMS, or OpenVMS; About 75%
mistakenly thought VMS was dying or was already dead. So I wrote this Mini-FAQ based mostly upon coffee-break questions of that week. I
have decided to keep the FAQ very general and less than 10 questions.
Edit: 2009-09-26 (fixed some grammar)
Questions and Answers
- What is the difference between VMS and
Nothing. Due to customer requests, VMS source code was opened-up
to paying customers around the same time it was ported from 32-bit
VAX to 64-bit Alpha (~1992). At that time, the product name and
version numbers flowed from VMS-5.5-2 to OpenVMS-6.2.
The most recent (2008) version is OpenVMS-8.3, which contains
some cool stuff including support for Intel's most recent
true 64-bit CPU called
- Do I need to port any code when
going from "VMS on VAX" to "OpenVMS on VAX"?
No because the two names represent the same OS but
anytime you consider jumping a major OS version number you should
always check with the vendor of your application software. If you authored your own software and still posses the source code then a
simple recompile then link should solve 99% of most problems (but
always do a trial port first). Going from VAX to Alpha is only a
tiny bit more complicated but is a no-brainer if you have access to your
A diary of my VAX to Alpha ports:
- I thought OpenVMS was going to be shut
No. This misconception started when Compaq announced the end
of the "VAX hardware" line in the last quarter of 2000. When
VMS was first released 1977, it only ran on the 32-bit VAX hardware
line, so many IS/IT people from that era cannot think about VMS
without also thinking about VAX. In 1992, Digital started
manufacturing 64-bit Alpha hardware and supported OpenVMS on both
- So how many hardware platforms does OpenVMS
(natively) run on?
Three for sure, possibly four.
- VAX (32-bit CISC)
Even though no new
VAX machines are being manufactured, OpenVMS
is still being supported on VAX by HP.
- Alpha (64-bit RISC)
Alpha systems will be manufactured after December-2006 but HP
still plans to support OpenVMS on Alpha up to the end of 2011.
Maybe longer depending upon customer demand.
- Itanium2 (64-bit EPIC)
This is Intel's latest dream chip for competition with IBM's
POWER/PowerPC line and Sun's Ultra SPARC. Note that
Itanium will be targeted
at the server market, which is why many consumers have never
heard of it. One implementation of Itanium is designed to
execute up to three 64-bit instruction streams in parallel so
stating that Itanium is 64-bit is really a misnomer. In this
case, it is
really 192 bit.
p.s. note that HP uses the name Integrity in the product names
rather than Itanium
- x86-64 (EM64T and/or AMD64)
This is a rumor that never goes away.
No one from OpenVMS Engineering has ever stated that they were porting
OpenVMS to x86-64 but
this rumor still persists. In addition, the popularity of Pentium compatible
technology combined with the fact that it continues to be more powerful
every year would make this rumor seem plausible.
ps-1: Contrary to popular belief,
EM64T and AMD64 are true 64-bit CPUs. Registers and all.
ps-2: in the late 1980's DEC
(Digital Equipment Corporation) did begin a trial port of VMS to
x86 under the project names of
When this project was cancelled, one of the project primes (Dave
Cutler) resurrected it for Bill Gates at Microsoft. This
resulted in a product known as Windows-NT (new technology) which
later became products like: Windows-2000, Windows-XP, Windows
2003 Server, Windows-Vista, Windows-7, etc. I only mention this to prove that the
porting rumor may not be so far fetched.
ps-3: check out this private site
for some compelling reasons:
- How is OpenVMS business doing in a world
dominated by hype from Windows/UNIX/LINUX?
Since HP merged with Compaq in 2002, the OpenVMS business has been
growing world wide by 10-12% per year. Since we are talking about an
annual gross amount in excess of 4 billion dollars, these numbers
are not something to be ignored.
(Observation: the biggest demand for OpenVMS technology is currently
coming from Europe. I find this strange since Europe is the
birthplace of LINUX).
- Prove to me that OpenVMS is not dying.
In 2005, Oracle released "Oracle 10g For OpenVMS on Alpha".
Oracle Corporation has never been known to waste money on foolish
ventures. On top of that, they still make a ton of money developing
Oracle-RDB on VAX, Alpha, and Itanium.
- What about all the freeware Open Source
software in the public domain? Doesn't most of it only run on
Windows or UNIX?
Most of it only runs on UNIX and has been ported to other platforms
including Windows. OpenVMS does support a UNIX "compatibility API
(application programming interface)" which is used to run many UNIX
with little, or no, modification.
- How does OpenVMS compare to UNIX and/or
First off, UNIX is almost 8 years older than VMS
although they were developed in the same decade.
Although LINUX is much newer UNIX-like product, it is not a new
operating system. In fact, it is just BSD UNIX applications with a
kernel. Click here for a side-by-side
comparison. All modern operating systems support Symmetric Multi
Processing (SMP) but OpenVMS is still the industry leader
What the UNIX world calls "a cluster" is no where close to what is happening
in an OpenVMS Cluster.
HP is (understandably) unwilling to increase OpenVMS sales by
relating to a horrible human tragedy so let me publish something
which HP will not:
There were more than a few OpenVMS
clusters running in the World Trade Towers on 9/11 (unfortunately, some
clusters were composed of nodes only found in buildings one and two).
Some European financial businesses operated OpenVMS Clusters with at
least one node in one of the Twin Towers with another located elsewhere,
like New Jersey.
These European businesses was very surprised as they watched the towers
fall on TV but never saw their OpenVMS clusters drop any transactions.
Official HP information:
Kitchener - Waterloo - Cambridge, Ontario, Canada.