V4R5 Arrives: Is it the Answer?

What to expect from the enhancements in Big Blue’s new OS

IBM's latest release of OS/400, V4R5, has advances in many areas, most notably, Logical Partitioning (LPAR), AS/400 Portable Application Solution Environment (PASE), Java and Operations Navigator. All these combine to make the AS/400 more open and easy to use as well as improve performance for the user. Here’s a glance at each of these topics.

It’s Only Logical, Watson

Logical Partitioning was added to the AS/400 with OS/400 V4R4, allowing customers to run multiple, independent OS/400 instances or partitions in n-way AS/400e 6xx, Sxx, and 7xx servers. The use of Logical Partitioning has allowed users to reduce IT overhead and associated costs.

For V4R5, IBM has extended LPAR support to include AS/400 8xx n-way servers. Something to keep in mind, however, is that the 8xx servers require OS/400 V4R5 at minimum. Therefore, you cannot have an 8xx server with V4R4 and V4R5 partitions, while you may have an Sxx, 6xx or 7xx with both V4R4 and V4R5 partitions. The total number of partitions that can be created on a single server has also been doubled, from 12 to 24 in the high-end 8xx servers.

With V4R5 you’ll be able to install the new operating system in a test partition and complete release testing prior to upgrading the operating system on the production partitions. But note that although OS/400 V4R5 can be installed in any partition, to take advantage of these partitioning enhancements, the primary partition must be upgraded to OS/400 V4R5. Updates to the Software License Management (SLM) APIs allow both customers and business partners to monitor an application usage count across the system rather than at partition level.

There has also been a huge step forward in OS/400 V4R5 partitioning management. It has been enhanced to ensure that secondary partitions shutdown normally when the primary partition is powered down. Although currently warning messages are issued if any secondary partitions are active when the primary partition is shutdown, some users elect to ignore these messages, resulting in the secondary partition shutdown ending abnormally and longer IPLs. The V4R5 enhancement will ensure that when the primary partition is shutdown, the secondary partitions are also shutdown normally.

With the new 8xx series hardware, customers will also benefit from being able to order an external stand-alone CD-ROM installation device, 7210-020, for secondary partitions. This device attaches to the AS/400 via a #2768 ultra SCSI IOA, and can be used as an alternate IPL device for secondary partitions. Unlike the internal CD-ROM drives, this external version has its own SCSI cable that allows the customer greater flexibility in placing the device and associated IOA in the system.

Although some of the new 270 models are available with multiple CPUs, LPAR will not be supported on these models as it is with the model 170s with OS/400 V4R4.

Setting the PASE


With V4R5, a number of changes have been implemented in PASE support, the most important being support for AIX 4.3.3. Others include:

  • Addition of shared libraries for C++ and Fortran runtime
  • New PASE locales using CCSID 1253 and iconv conversions for euro currency symbol support
  • Addition of the "sh" shell
  • Directories and symbolic links are moved to /QOpenSys to provide support for case sensitive names

  • The port of Lotus Domino demonstrates AS/400's success in migrating major Unix applications to its AS/400 Integrated Language Environment (ILE). While many applications continue to move to the AS/400 in this manner, others have specific Unix requirements or are designed with highly compute intensive demands that favor a Unix runtime environment.

    RS/6000 and AS/400's common hardware base includes the PowerPC AS processor's ability to switch between runtime modes. PASE exploits this capability to execute 32-bit AIX applications on the AS/400. Keep in mind that PASE is not designed to be an operating system in its own right and uses OS/400 systems management, middleware and database functions.

    AS/400 PASE adds another porting option for highly compute intensive Unix applications that can improve the time-to-market for Unix application ports. All this combines to make the AS/400 even more open and helps quash the myth of it as a closed, proprietary system.

    Java Jive

    New access classes provide FTP client and service program call interfaces. The FTP class provides a programmable interface to FTP functions. You no longer have to use java.runtime.exec() or tell your users to run FTP commands in a separate application. That is, you can program FTP functions directly into your application.


    From within a program, you can:
  • Connect to an FTP server
  • Send commands to the server
  • List the files in a directory
  • Get files from the server
  • Put files to the server

  • While the FTP class is a generic FTP interface, the AS400FTP subclass is written specifically for the FTP server on the AS/400, because it understands the semantics of the FTP server on the AS/400. AS400FTP also ties into the security facilities of the AS/400 Toolbox for Java. As with other AS/400 Toolbox for Java classes, AS400FTP depends on the AS400 object for system name, user ID and password.

    New HTML and servlet classes make it easier to write servlets. AS/400 Toolbox for Java HTML classes assist you in setting up forms and tables for HTML pages. These classes can work with servlet classes to get data from the AS/400 server. However, they can also be used alone if you supply the table or form data.


    The HTML classes make it easier to make HTML forms, tables, and other elements:
  • HTML Form classes help you make forms more easily than CGI scripting
  • HTML Hyperlink class helps you create links within your HTML page
  • HTML Text class allows you to access the font properties within your HTML page
  • HTML Table classes help you make tables for your HTML pages
  • URL Encoder class encodes delimiters to use in a URL string

  • Proxy support can make it easier to run Toolbox classes in a three-tier environment. AS/400 Toolbox for Java now contains proxy support for some classes. Proxy support is the processing that AS/400 Toolbox for Java needs to carry out a task on a Java virtual machine other than the Java virtual machine where the application is located.

    Before proxy support, the classes containing the public interface and all classes to process a request were run in the same Java virtual machine as the application. With proxy support, only the public interface needs to be with the application. The classes necessary to process a request can be running on another machine. Proxy support does not change the public interface. The same program can run with either the proxy version of AS/400 Toolbox for Java or the traditional version.

    The goal of the multiple-tier proxy scenario is to make the downloaded jar file as small as possible so that downloading this file from an applet takes less time. An additional benefit of proxy support is that fewer ports have to be opened through your firewall.

    Traditionally, when using the AS/400 Toolbox for Java it was necessary to open multiple ports because command call uses a different port than JDBC, which uses a different port than print, etc., and each of these ports must be allowed through the firewall. With proxy support all the data flows through the same port. The jt400Proxy.jar is shipped with the rest of the traditional AS/400 Toolbox for Java and the proxy classes are pure Java so they can run on any machine with a Java virtual machine.

    V4R5 now supports Linux, Java 2 (1.2.2 version of Java) and Swing 1.1 (GUI components). The PDML runtime environment now uses Swing 1.1. This allows you to take advantage of enhanced functions and performance available in the latest release of the Java Foundation Classes. The GUI Builder generates help in a composite file for easier development.

     GUI Builder and Resource Script Converter Enhancements

  • Cut, copy and paste support
  • Undo and redo support
  • Generation of Java source for event handlers
  • Support for context menus, menubars and toolbars
  • Ability to browse for images
  • New panels now contain OK, Cancel, and Help buttons by default
  • Resizable controls within resizable panels
  • Ability to reference panels in other PDML files
  • Spin button control
  • Ability to equalize space between selected fields
  • Hide and show events for buttons
  • Icon placement on buttons
  • Custom cell editors/renderers for tables and lists
  • Selected and deselected events for list items
  • Table column heading alignment in tables
  • Support for multiple icons on tree nodes
  • Improved Javadoc and more coding examples
    VisualAge for Java has been enabled for remote debugging of Enterprise Java Beans running in Websphere. V4R5 provides the capability to launch a Java debug session into an already running Java Virtual Machine. In Java 2 SDK (J2SDK) Standard Edition 1.2, the Java Virtual Machine Debug Interface (JVMDI) is part of Sun Microsystems platform APIs. JVMDI allows anyone to write a Java debugger for AS/400 in AS/400 C code. The debugger doesn’t need to know the internal structure of the Java virtual machine, and can’t harm the Java virtual machine because it uses JVMDI interfaces.

    The debugger runs in the same multithread capable job as the Java virtual machine. It uses Java Native Interface (JNI) Invocation APIs to create a Java virtual machine. Typical debug facilities are available, such as setting breakpoints, stepping, displaying variables and changing variables. The debugger handles communication between the job where the Java virtual machine is running and a job handling the user interface. This user interface is either on your AS/400 or another system. A service program, called QJVAJVMDI that resides in the QSYS library, supports the JVMDI functions.

    Java seems to be the way of the AS/400’s future and should breathe new life into what many people mistake for an old, tired platform. IBM's positioning of the AS/400 as a Java machine can only bring new converts and will ensure the longevity of this reliable workhorse.

    Navigation Wizards

    The AS/400 required a facelift to its well known "green-screen" to remain competitive with the point-and-click GUIs offered by its competitors, so starting in V3R7 IBM equipped it with Operations Navigator. It’s been continually enhanced in subsequent releases and is now a permanent part of OS/400. Slowly but surely, System Service Tools (SST) and its command line/options menus are being phased out and replaced by point and click within Operations Navigator.

    For V4R5, more functionality has been shifted from the command line into Operations Navigator. DASD Management, once the exclusive domain of the command line, has been added to the interface. The user can add new disk units, create new disk pools (ASPs), view and manipulate large DASD configurations as well as perform many disk maintenance functions. Wizards guide you through disk functions and include easy to use help menus. However, actions that require a DST limited paging environment, such as replacing a disk, are NOT supported.

    Tasks such as Management Central, Database Management, Directory Services, TCP/IP Protocol Management, Windows INS Administration and Cryptography Resource Management have also received enhancements in the V4R5 release of Operations Navigator.

    At this release don't expect to throw out your Twinax terminal for good, however. Despite some of the servers being touted as having a zero interactive feature you still require the green-screen interface for many functions. This means that machines with the zero interactive feature can still support a single interactive session for use as a system console and will require it for DST. It seems that IBM is moving toward a strict GUI environment and while some people will still want to cling to the command line, keep in mind that the System/36 was great in its day, but would you still want to have it as your core business machine? It's time to modernize your system. The switch to Operations Navigator can only help complete the modernization of the platform and should be embraced whole-heartedly.

    These are only some of the enhancements you’ll find in OS/400 V4R5. Overall, V4R5 looks to be the AS/400 division’s hottest release of hardware and software to date, and the trends in place should ensure the future survival and growth of one of the most overlooked platform around.

    Related Editorial:

  • IBM Delivers New AS/400 Models, OS/400 V4R5

    Related Information:

  • IBM AS/400 Page (new window)