[Vms.sig-hu] Very Nice OpenVMS Pearl - OpenVMS Press article -Hack-proof and crash resistant - have you discovered the OS world's best-kept secret? OK for public distribution (fwd)

[Fodor Zsuzsa]

---------- Továbbított levél ----------
Dátum: Tue, 13 Jul 2004 09:26:47 -0400
Feladó: Skonetski, Susan <susan.skonetski at hp.com>
Címzett: Skonetski, Susan <susan.skonetski at hp.com>
Tárgy: Very Nice OpenVMS Pearl - OpenVMS Press article -Hack-proof 
and crash resistant - have you discovered the OS world's best-kept 
secret?  OK for public distribution

 http://www.computerweekly.com/articles/article.asp?liArticleID=131808

Many thanks to OpenVMS Champion Colin Butcher who wrote this 
article.

Warm Regards, 
Sue


_________________________________________________________
_________

Hack-proof and crash resistant - have you discovered the OS world's
best-kept secret?

 
OpenVMS offers unmatched robustness for business-critical apps 

OpenVMS (originally known as VMS) is probably the best designed and 
most
robust general purpose operating system in existence. It is also one of
the least-known and appreciated, simply because it works quietly in the
background without drama, unlike its noisier and more fussy siblings 
and
offspring. 

You will typically find OpenVMS in any environment that is serious about
high availability, disaster tolerance, security, performance and
scalability, especially when running real-time applications. Users
include banks, stock exchanges, healthcare, manufacturing, aerospace,
online billing, lotteries, chip manufacturing, oil and gas production,
power stations, railways, government and secure public sector
applications. In short, anything that really has to work.

Uptime measured in years

OpenVMS system uptimes are often measured in years - it being a 
point of
honour to avoid rebooting and causing disruption unless utterly
essential. 

There are clusters out there with uninterrupted service uptimes in
excess of 15 years, even if individual machines have been occasionally
rebooted, upgraded or replaced. That is a far cry from today's "reboot
and restart" culture, where users seem willing to tolerate disruption to
service - indeed, they have come to expect it. If only they were aware
there is a better way. OpenVMS is one of the industry's best-kept
secrets - those in the know would not consider using anything else for
business-critical systems.

OpenVMS runs on three hardware platforms: Vax (32-bit Cisc), Alpha
(64-bit Risc) and Itanium (64-bit Epic). A system disc from any Alpha
will boot and run on any other Alpha. The same goes for Vaxes, 
including
software-emulated Vaxes. Likewise for the latest HP Integrity servers.
OpenVMS will boot and run on anything from an RX2600 to a 
Superdome.
This scalability and interoperability derives from the excellent
internal architectural structure of OpenVMS.

The bigger machines (Superdome, GS1280, etc) can be hard-partitioned 
to
make a group of hardware resources inaccessible from other partitions.
OpenVMS also supports soft partitions, using a mechanism known as
Galaxy. This allows CPU resources to be dynamically reallocated 
between
soft partitions to meet changing workloads. 

Partitioned systems are often used for server consolidation. Extending
that by dynamic reallocation of hardware resources leads us to adaptive
computing.

Pioneer of clustering

OpenVMS pioneered clustering in the mid-1980s and is still the standard
to which all others aspire. It provides a "shared everything" model with
minimal cluster state transition latency if a cluster member fails. 

This model allows all the resources in a cluster to be used
concurrently, not in a failover or standby mode. There are many
disaster-tolerant, split-site clusters in operation that continue to
provide uninterrupted service without loss of data, even when whole
sites fail. The largest supported OpenVMS cluster is 96 nodes - where
each node can be a large multiprocessor system.

Cluster interconnects can be anything from the original CI hardware to
Gigabit Ethernet, or even Galactic memory in a soft-partitioned system. 

Many operations staff find using better-known operating systems
frustrating in comparison to OpenVMS. The issues are primarily poor
availability and reliability, combined with the difficulty of obtaining
performance analysis and fault log data for capacity planning and fault
analysis purposes. OpenVMS is generally seen as the gold standard for
such things.

For instance, OpenVMS comes with essential tools and facilities (most
prominently, image back-up and restore) built in, rather than having to
be added on. In most cases, you simply install it, configure it for your
workload, add your applications and system-management utilities
(typically DCL command files), then run it as a black box operational
environment.

As an operating system with a real-time pre-emptive scheduling
mechanism, OpenVMS has always been capable of handling complex 
real-time
events. The interrupt-driven I/O subsystem design aims for minimal
latency, so OpenVMS is capable of exceedingly high, sustained I/O
throughput, especially with V7.3-2 on Alpha EV7 (Marvel) systems. It
will be interesting to see how V8.2 on Alpha and the Integrity server
range compare when it is released.

As a software development environment, OpenVMS provides a rich set 
of
features and programming languages, debug facilities and operating
system services.

A key aspect of the OpenVMS design is the "calling standard" that 
allows
code modules to be written in any language and code to call routines
written in other languages. This is a great aid to application
portability and, of course, to debugging code. 

It is the architectural structures that make it easy to optimise memory
use with shared image libraries and also to deliver software
compatibility between versions of the operating system without the 
need
to recompile and relink applications.

Although off-the-shelf package-based products may be in fashion,
designing and implementing your own is the only way to utilise the
capabilities of the underlying platform. 

This is especially true for high-availability environments where the
features have to be built into the application and need to be reflected
throughout the system architecture. Time spent investigating, testing,
customising and deploying a package can often be better spent 
developing
your own product layered on top of a system designed around the 
minimum
components that fit the overall application architecture.

OpenVMS also has excellent security. A hacking contest was held at the
DefCon 9 conference in July 2001, where the winner was not NT, XP,
Solaris, Linux or BSD. It was VMS, which was rated "cool and
unhackable". 

Not legacy nor unfashionable

OpenVMS generally appeals to those who take pride in using computer
systems to do a job effectively and reliably, rather than those who want
to live at the bleeding edge with the newest (and often immature)
technology.

Probably the biggest challenge for OpenVMS to overcome is its lack of
public visibility. This has led to the perception of it being old, or
legacy, or simply unfashionable, whereas in fact it is still under major
development. This includes secure and stable implementations of
commonly-used software such as Apache, Java, Mozilla, Perl, Python 
and
XML. 

End-users, system managers and software developers want and need 
to see
sufficient advertising of OpenVMS' strengths and capabilities so that
those at board level can realise that in many cases it is a better and
more cost-effective way of delivering secure, ultra-reliable and
scalable business-critical systems than the more fashionable and
better-promoted alternatives.

Now the new HP has begun to settle down, and with the porting work 
to
the Integrity server range almost complete, the expectation is that we
will see the many benefits of using OpenVMS-based systems being 
actively
promoted. OpenVMS has a long life ahead of it, once the current and
future generations of decision-makers realise what it can do for their
businesses.

Colin Butcher is technical director of XDelta and board member of the HP
User Group