The Value of VM for VSE Enterprises

December 1997


"They're the leaders: The businesses that get the most from information technology. They're creating flexible, fast-paced and responsive systems for achieving optimal business value. They're leveraging the Internet and distributed systems, while also managing their ever-growing and increasingly complex operations."
Information Week, Sept. 22, 1997

IT Challenges: Today and Tomorrow

In today's accelerating and highly competitive business environment, the importance of Information Technology solutions only grows. Enterprises are facing rough challenges both now and beyond the Year 2000.

IT professionals must simultaneously deliver the benefits of client/server and network computing, and support new applications while reducing the overall cost of delivery. They must make critical decisions. The leaders are achieving all of this, often with solutions that at first glance may seem surprising – like adding VM.

Current VSE installations are faced with the challenge of the next millennium and how the new age of Electronic Business (e- business) will influence them. Some are under pressure to "downsize" to a client/server environment. There must be improved portability across platforms as well as robust system management tools to handle the increased level of complexity. Some are already on their way and some are not. Armed with the valuable and timely information that follows, IT managers can decide for themselves: Where is the right place for me? They can also decide that the VSE and S/390® platform, coupled with the value that VM/ESA® provides in today's environment, may be just the key for which they are looking.

It Has Never Been a Better Time to be a VM and VSE Customer

IBM has responded to the needs of IT managers with fresh strategies, products and commitments. With our increased investment in IBM Business Partners, attractively priced Enterprise Server Offerings, performance improvements, new products and improved customer support, it has never been easier to bring in or upgrade to the VM and VSE operating environment.

IBM estimates 8,000,000 people use VM every day. There are over 14,000 licenses in 87 countries. Because these VM systems run on the entire S/390 processor line, VM offers one of the greatest ranges of growth over all other operating systems.

For 25 years, customers have achieved success with VM due to its classic strengths of central server architecture, application development and test, and support of guest operating systems. Companies use VM for data management, office systems, communications, business intelligence and much more.

Many customers choose VM because it can solve a wide range of business challenges quickly and efficiently. As such, VM is emerging as a leading network computing server for both the Internet and intranets, as well as an excellent platform for Year 2000 and Euro readiness projects.

IBM Enhances the Popular VM Platform

IBM has announced a strategy to address the needs of medium-sized S/390 enterprises which incorporates significant new opportunities for the VSE customers:

  • Strengthening relationships with IBM Business Partners worldwide providing more support and skills to customers
  • Attractively-priced Enterprise Server Offerings (ESOs) are offered in many countries to enable customers to get current with new hardware and software with optional services and financing available
  • A new release of VSE/ESA™, which now includes a native TCP/IP
  • A new release of VM/ESA which includes TCP/IP improvements, Java™ with the option to use the NetRexx™ productivity feature and MQSeries® interface clients
  • Offerings are available which enable VM and VSE customers to gain access to new applications based on UNIX® and/or OS/390™, without migrating current applications from VM and VSE
  • Fifteen new models of the S/390 Multiprise 2000™ available in attractively priced offerings that include software and services.

The Value of VM for VSE

"Information Technology provides the core genetic code for the evolution of business. Companies that don't leverage IT effectively– and keep up with the pace of change – will fail to meet the standards of their marketplace."
Dennis O'Leary,
Executive VP and CIO, Chase Manhattan Bank,
Information Week, Sept. 22, 1997

VM: A Long Lasting, Versatile Solution

IBM large systems servers, commonly referred to as mainframes, use three main operating systems to manage the hardware and the software running on them. They are VSE/ESA for small to medium-size enterprises, OS/390 (MVS™) for enterprises with greater availability and higher volume needs, and a unique operating system, VM/ESA, that augments both environments.

IBM introduced the Virtual Machine (VM) construct in the late 1960s to allow users to run numerous systems on one physical machine. VM can also play the role of either, or both, client and server for applications. Thus, a company could be running three (or more) VSE operating systems simultaneously. One could be their production system, a second could be used for changes to mission-critical applications, and a third for testing today's applications with its system clock set to the date of February 29, 2000! All three, running simultaneously, but separately, are isolated from others but still share resources. For example, a database running natively on VM can serve data to all three VSE images at the same time.

IBM has improved VM steadily over the years, earning high scores for quality and customer satisfaction. The unique features of the VM operating system permit an information systems department to do more with less, a key advantage to any business.

VM Provides Flexibility for Year 2000 and Beyond

VM/ESA provides the flexibility to adapt to the rapidly changing business environment while conserving hardware and software expenditures. If you look at the upcoming Year 2000 transition, you will see that Year 2000 problems manifest themselves at many levels. First the hardware platform must be enabled. Second, the operating system must be ready so that applications and operations will be able to execute properly. Last and most important, the bulk of the work lies in analyzing, updating and testing the application programs. Failure to do so may result in a disaster from which a business cannot recover.

Some organizations have attempted to migrate, or are in the process of a migration to a distributed, or alternate platform. These organizations are faced with the daunting task of selecting new software solutions, installing it on an unfamiliar platform, tailoring the package to meet the needs of their business and training their people to use it... all while making sure it is Year 2000 ready and in production before repercussions impact the system. It is often much simpler, less risky and less expensive to prepare the S/390, the system upon which your business was built, for the Year 2000.

The Year 2000 problem is not restricted exclusively to the mainframe (S/390). It affects all aspects of the computer industry. However, with the power of VM, S/390 customers are better equipped to prepare for the millennium.

Using VM to support multiple VSE images offers the flexibility to define VSE images on demand, when they are needed. Under global pressure of the Year 2000 and imminent European monetary conversions, you could realize savings in both productivity and expense when compared to use of logical partitions (LPARs) or separate physical systems. Adding VM to your VSE system gives you these benefits:

  • Dynamically change and add test environments during normal business hours without affecting your production environment
  • No additional VSE software licenses required
  • More test scenarios are possible within a given hardware configuration – optimizing your hardware investment.

Whether your critical applications are centralized or distributed, isn't it imperative that these applications are reliable and available? Injecting change, (be it service, enhancements or new levels) to critical applications calls for the establishment of a test environment that will not disrupt the current production environment. The VM guest support capability provides an ideal test environment. VM conserves time and hardware for testing VSE, TPF, MVS, OS/390 or even VM itself.

VM Enhances Productivity

By adding VM to VSE, IT personnel can do more during the day and minimize off-shift programming, testing and migration. Application development and testing can not only be isolated from VSE production environments, but VM also adds robust interactive productivity tools included in the base that VSE programmers can exploit:

  • XEDIT – A full screen editor, powerful yet easy to use. XEDIT is clearly superior to VSE's native ICCF editor and in fact, is the editor preferred by MVS, VSE and UNIX programmers alike.
  • Conversation Monitoring System (CMS) In conjunction with the minidisk and the hierarchical shared file systems, CMS provides an excellent interactive environment for development and production applications.
  • REXX – A high level multiplatform programming language – easy to learn and easy to use, improving programmer productivity.
  • CMS Pipelines – An extension to REXX that employs pipes similar to those in a UNIX shell, allowing rapid implementation of complex applications.
  • Java and Java Development Kit (JDK) – Provides for more rapid development and portability of Internet applications.
  • NetRexx – Offers a human-oriented language for e- business or Web applications, without sacrificing the portability of Java.
  • Common Gateway Interface (CGI) scripts – Can be written in REXX on VM. A productivity advantage over using assembler for those same scripts in VSE, enabling faster deployment of Web-based applications.

In times when competitive edge is measured in months, if not weeks, business success or failure can depend on nimbleness on the Network. These tools pave your ramp to the Information Superhighway, where speed to market and efficiency are a necessity.

VM Web Serving and Connectivity

Beyond Software, Inc.™ and Sterling Software Inc.™ working with IBM, offer full function Web serving products for the S/390 platform. Their Web servers, along with the browser of your choice, can link your applications and data to new markets with security and reliability.

VSE provides TCP/IP capabilities; however, VM extends these capabilities with a more robust TCP/IP to enable VSE to conduct business electronically. VM, in conjunction with products from these IBM Business Partners, provides the following services for VSE:

  • Session management and security control required to enable your CICS® applications for the Web, either external (Internet) or internal (intranet). Some of these products will let you Web-enable any or all legacy applications without re-engineering, all the while retaining your existing security scheme.
  • Robust security and encryption services for conducting true e-commerce over the Internet.
  • REXX and NetRexx provide improved programmer productivity. These languages let you exploit the Internet faster than possible with Assembler and/or Java.
  • VM can boot and serve hundreds, even thousands of IBM Network Stations™. These are thin clients with no moving parts – ideal for CICS transactions, be they 3270 or Web- enabled applications.

Your only alternative to Web serving with VM is to establish distributed NT or UNIX front-end processors to provide the middleware functions to your VSE host. In doing this, however, you will sacrifice some functions which these alternate platforms lack. First and foremost are the REXX and NetRexx languages. Another example is that most distributed middle-ware products cannot handle full screen 3270 applications and they limit you to one HTML form per 3270 screen. Both of these 3270 restrictions are alleviated by VM:Webserver Gateway™ from Sterling Software. But more importantly, with the distributed approach, you will forgo the undisputed strengths of the S/390 for your Web-based applications:

  • Highly reliable hardware, operating system and subsystems which are up and running around the clock, available to browsers in any time zone.
  • Smooth, non-disruptive growth in capacity (also referred to as scalability) which averts bottlenecks which can hamper the growth of your e-business.
  • Existing data center infrastructure which includes not only hardware but people, policies and practices as well. Capitalize on the skills and disciplines on which you have built your business.

In addition to Web serving, VM has always brought vitality to VSE, enhancing its ability to connect to the rest of the data processing world. Even though VSE has had native implementations of TCP/IP, VTAM and LANRES for some time, VM has always provided an edge in these areas:

  • TCP/IP for VM enhances a VSE network with NFS, dynamic routing, SNMP instrumentation and a secure sockets layer – core requirements for e-business over the Internet.
  • SNA Network Interconnection (SNI) isolates and protects one SNA network from the operations of other networks, an e- business necessity for VSE companies with the SNA protocol.
  • As LAN applications become more critical to business operations, VSE customers need to introduce the LAN environment to the discipline of the enterprise. LAN File Server permits integration and consolidation of data from NT, UNIX and OS/2® Servers onto the S/390. LAN users can then enjoy the availability, reliability and systems management capabilities of the mainframe.

Whatever the task, VM puts more interfaces, protocols and clients into the hands of VSE. Short of a full blown OS/390 server, the combination of VM and VSE cannot be beat!

Improve Performance and System Management with VM

VM improves the monitoring and tuning of your entire system with a plethora of performance management tools. In fact, system management can be improved without sacrificing system performance through use of VM features such as: Minidisk cache, Virtual Disk in storage, Preferred VSE Guests and CCW fastpath. In some cases, throughput may even be enhanced.

VM's flexibility allows you to optimize and balance CPU, memory and paging subsystems between VSE images. With DB2®, for example, VM provides a technique known as "guest sharing" whereby connections between the VSE guests on a DB2 Server are virtualized utilizing an efficient protocol known as inter-user communication vehicle (IUCV). In this case, VM avoids the need for physical hardware channels and eliminates SNA overhead. VM also provides support for Data Spaces which can improve the performance of DB2 and other servers, for example, the CMS Shared File System.

VM offers many functions that VSE customers would otherwise purchase from a third party. For example:

  • VM's virtual disk fixes the VSE lockfile into the central storage of the processor, effectively eliminating the extra I/O required for disk sharing.
  • Hardware Page Notification notifies support staff of system events via a pager service. This is a built-in, no-charge feature of VM and the Multiprise 2000.

But perhaps the most important to the VSE customer with multiple VSE images is VM's exclusive ability to monitor the VSE images and tune resources system-wide.

Getting More Out of Your Hardware Investment

With concerns for the Year 2000, the Euro monetary imperative and Web application initiatives, it has never been more important to be able to quickly establish and isolate different production and test systems on the S/390 platform. VSE customers can no longer afford to sacrifice VM for the rigidity of LPAR. Most VSE systems do not even have the central storage required to establish an image for Year 2000 readiness projects, not to mention the processor channels and device controllers. Even VSE customers that have VM seem to forget these simple facts:

  • A small VSE/ESA test system requires 20MB of dedicated real storage just to IPL.
  • Each VSE image in an LPAR environment requires its own dedicated channel and non-SNA terminal controller.
  • For VSE systems with parallel attached I/O devices, each logical partition requires its own dedicated channel to those I/O devices. Typically, three to eight channels and adapters are needed to access disk, tape and printers.
  • Channel-to-channel connections between VSE images require at least two parallel channels and a 3088, or two ESCON® channels on processors with that capability.
  • LPAR overhead is equivalent to that of VM.

All of this adds up to cost: hardware, maintenance and especially time, not to mention a desperate lack of flexibility and responsiveness. We have already seen second and third shift downtime dissipate to a very brief window of the very early morning hours. As the world comes online, weekends can no longer be dedicated to the IS staff.

On a typical S/390 in LPAR mode, with one production and one test VSE, it is straight forward to add VM without impacting production and, in effect, give the test VSE memory to VM. VM, in turn, will virtualize the system resources, allowing the definition of as many test scenarios as required to meet the deadlines. The only cost is additional disk for paging. But while VM guests may require paging packs, they do not require their own channel paths to device controllers, a much more expensive resource. What's more, communication between the various VSE guests is simple and efficient with Virtual Channel-to-channel (VCTC) connections. Built right into VM, VCTC requires no additional hardware or software.

VM also provides additional functions to VSE users of IBM disk and tape subsystems. For example, VSE can take advantage of the high availability and performance of the RAMAC® Virtual Array (RVA) disk subsystem. But only with VM can VSE exploit the subsystem to its fullest potential. An exclusive feature of the RVA known as Snapshot for VM, copies disk volumes, data bases and entire VSE systems in minutes, if not seconds, all with a negligible amount of real disk consumption. Snapshot and VM makes a terrific solution for the shrinking batch window. Volume copies can be snapped at midnight, on-line systems brought up, and the tape dump can be deferred until first shift when there is no contention for drives.

The combination of VM and Snapshot also provide an ideal environment for Year 2000 testing. "Snapped" VSE disk volumes can be modified, IPLed and tested by virtual VSE guests over and over again, without impacting production, and without having to acquire and maintain additional disk drives. The combination of VM and Snapshot may in fact be the only alternative for many VSE customers that are still trying to prepare for the Year 2000.

At this point in the millennium, most all VSE customers have multiple VSE images. VM conserves hardware and reduces associated costs without degrading performance. At the same time it expands flexibility – enabling the VSE system to respond and adapt to new business requirements.

Packaged Solutions Available

Customers have reaffirmed that the packages solution continues to be the preferred approach in most countries to deliver integrated solutions at the most attractive prices. The packages, known as Enterprise Server Offerings (ESO), include hardware, software, maintenance, services and customer financing, and are sold by IBM sales representatives and IBM Business Partners. The ESO provides attractive and expeditious acquisition for the S/390 Multiprise 2000, S/390 Parallel Enterprise Server – Generation 3™ or S/390 Parallel Enterprise Server – Generation 4™.

In general, solution packages provide customers with many advantages, including:

  • Complete package for ease-of-acquisition
  • Exploitation of advanced technology
  • Predictable price and lower life-cycle costs
  • Availability of support services to lower costs of computing
  • Single invoice, single contract and single interface to IBM
  • Financing options when migrating to the ESA versions of S/390 Year 2000-ready operating systems.

The ESO may be the right choice for your business because it is an affordable, simple and low risk way to position your company for the advanced functionality of today's hardware and software.


The total value for VSE customers running with VM is found in VM's original strengths and the enhancements offered in the most recent releases.

These can be summed up in five main value points that describe why bringing VM/ESA into a current VSE environment can help IT managers face today's problems, as well as tomorrow's challenges. These value points are:

  • Flexibility – the capability to shrink, or grow, a system as your business requires
  • Maximum utilization of your human and IT system resources – with current levels of the operating systems you can take advantage of Internet/intranet, client/server, e- business and new applications (even UNIX)
  • Cost effectiveness – purchasing technology that reduces the need for additional hardware purchases such as I/O devices, processors and data storage
  • Increasing access to your information and the latest hot technologies
  • Increasing control – managing your IT resources more effectively – meeting the Year 2000 challenge.

©International Business Machines Corporation 1997

IBM Corporation
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Printed in the United States of America, 12-97
All Rights Reserved

This publication was produced in the United States. IBM may not offer the products, services or features discussed in this document in other countries, and the information may be subject to change without notice. Consult your local IBM business contact for information on IBM products or services available in your area.

Information concerning non-IBM products was obtained from the suppliers of those products, their published announcements or other publicly available sources. IBM has not tested those products and cannot confirm the accuracy of performance, compatibility, or any other claims related to non-IBM products. Questions regarding the capabilities of non-IBM products should be addressed to the suppliers of those products.

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