as400 tutorial by sofarsogood



                                 The AS/400
        With 40% of new AS/400 ERP systems and 30% of new AS/400 Domino systems being sold
        to sites with no previous AS/400 installation, many IT staff outside IBM’s traditional domain
           are having to face this system for the first time. Why are people choosing the AS/400 over
                     alternative servers, and what are the implications for the IT manager?

                                                                                                                By Andrew Ward

     W          hen initially launched, the
                AS/400 suffered something
                of a mixed reception, and
     may well have been dismissed by
                                               ferent models are balanced in different
                                               ways, so that some are more suited to
                                               running dumb-terminal applications,
                                               while others are better for running to-
                                                                                          AS/400 is also expensive to own and
                                                                                          difficult to manage. In the same sur-
                                                                                          vey, the AS/400 took the mid-ground
                                                                                          on cost of acquisition, with Unix instal-
     many within the IT community as           day’s server applications with higher      lations being more expensive and NT
     something only of interest to the loyal   processing demands.                        systems cheaper.
     IBM customer. But since then, the            Dont’ let the mention of dumb ter-          But the AS/400 also took first place
     hardware has undergone a substantial      minals revive the idea that this is old-   in two important categories - customer
     and complete redesign, and the            fashioned proprietary technology.          satisfaction, and speed and consis-
     AS/400 is now one of the most ad-         Although IBM standards can still be        tency of application deployment. The
     vanced computing platforms avail-         supported, the AS/400e range, together     survey revealed that application de-
     able. It is the only true 64-bit          with the current operating system ver-     ployment on the AS/400 actually took
     mainstream system - the hardware,         sion (4.3), uses modern open standards     one third of the time that it did on Unix
     operating system and even applica-        such as Ethernet and TCP/IP. An            and NT systems. This highlights an
     tions are 64-bit throughout.              AS/400e can be considered to be a          extremely important benefit from the
         In terms of positioning, it makes     black box sitting on the network (and      IT manager’s point of view - the low
     most sense to think of the AS/400 as a    indeed they are black) providing just      amount of hands-on administration
     server, competing with high-end PC        the same services as you might expect      that the AS/400 requires, both to set it
     servers and Unix servers from vendors     from an NT, Unix or Linux system.          up and to keep it running. And what
     such as HP, Compaq, Sun and even                                                     little administration that does need to
     IBM itself. But the AS/400 is also ex-    Benefits                                   be done, can be carried out remotely,
     tremely scalable, from entry-level sys-                                              making the AS/400 an ideal choice for
     tems on a par with NT servers                This rather begs the question as to     branch and overseas offices where
     supporting just one or two hundred        why anyone would choose an                 there may be fewer IT support re-
     users, right up to models delivering      AS/400e system over any of the alter-      sources. Indeed, it’s quite common to
     mainframe performance. Lotus Dom-         natives, and the answer lies with total    find AS/400 sites that have no IT per-
     ino running on the AS/400 has pro-        cost of ownership (TCO). Several ven-      sonnel at all, something unimaginable
     duced world-beating benchmarks            dors, and Microsoft in particular, have    with a large PC LAN.
     with 27,000 users.                        jumped onto the TCO bandwagon in               Other benefits that customers, ana-
         The current AS/400 product range      recent years, but according to an Aber-    lysts and surveys suggest as being im-
     has adopted a letter e suffix - AS/400e   deen Group report the AS/400 divi-         portant are reliability, security and
     - the e being designed to associate the   sion at IBM has consistently focused on    scalability - a list which probably looks
     AS/400 range with modern applica-         lowering TCO for over a decade. In a       rather familiar, as being a list of those
     tions such as e-business and e-com-       survey by IDC of different ERP plat-       attributes which PC servers and oper-
     merce. Within this range, there are a     forms including Unix, Windows NT           ating systems would most like to have.
     large number of different models,         and the AS/400, the AS/400 was             Support is also important - and the
     which vary primarily in terms of proc-    shown to have the lowest TCO. This         AS/400 is supported in over 150 coun-
     essor and memory architecture, and        ought to go some way to dispel another     tries and in 51 national language ver-
     hence the performance delivered. Dif-     myth that, being proprietary, the          sions.

Issue 106 (April 1999) Page 9
                                               PC Network Advisor                                                           File: T1403.1

     App Availability                               AS/400, because it already includes its      fied. The template will be automat-
                                                    own - DB2/400 - which, as you can            ically recompiled into the new ma-
         Clearly, boasting the lowest cost of       surmise from the name, is a version of       chine-specific instruction set and your
     computing is of little use if a platform       IBM’s DB2. Because it is very tightly        application will take advantage of any
     won’t run the application you want.            integrated with the operating system,        performance improvements that the
     But today, all leading ERP vendors             performance is higher than a third-          new platform has to offer. If the pro-
     have ported their packages to the              party vendor could expect to achieve.        gram template had been deleted (for
     AS/400, and there are over 150 other                                                        example, to save hard drive space),
     ISV (independent software vendor) so-          64-bit Computing                             then the original application will need
     lutions available, and that’s on top of                                                     to be re-compiled to make a new pro-
     IBM’s own offerings such as various               IBM adopted an interesting tech-          gram template.
     vertical market solutions and Lotus            nique to isolate AS/400 software from           This technique of compiling to an
     Domino. Within the USA, 45% of ERP             the underlying hardware, which ex-           intermediate form probably sounds fa-
     solutions sold on AS/400 are now go-           plains how its engineers were able to        miliar, because that’s the way Java
     ing to new AS/400 accounts - in                update the AS/400 platform without           works, with the intermediate form in
     Europe, the figure is slightly lower at        anyone having to change their applica-       the case of Java being known as Java
     40%. And worldwide, the figure for             tions, and how those applications in-        Byte Code. An important feature of the
     Domino systems on AS/400s being                stantly became true 64-bit.                  MI is that it can be extended (but al-
     sold into new AS/400 accounts has                 Instead of a traditional operating        ways retains backwards-compatibil-
     reached 30%.                                   system API, which has hard-coded             ity), so to support Java, IBM extended
         Perhaps even more interesting is           into it some of the characteristics of the   the MI to include Java Byte Code. The
     the Java support now built into the            underlying hardware (such as the             result is the fastest JVM of any operat-
     AS/400’s operating system (OS/400) -           number of bits in a register), the           ing system.
     in fact, it’s the fastest JVM (Java Virtual    AS/400 uses a hardware-independent
     Machine) of any operating system.              machine interface, or MI. This object-       Management
     This Java support means that AS/400            oriented interface is quite independent
     owners have access to some of the most         of any aspect of the processor. AS/400           Shipped with OS/400 is a client ap-
     modern applications, such as the ob-           applications are compiled into an in-        plication called Management Central
     ject-oriented databases written in Java        termediate form known as a program           which provides an up-to-date Win-
     from Cloudscape and DataBahn,                  template, which is in effect a list of MI    dows 95-style interface to many
     which have both been ported.                   instructions. On the first occasion that     AS/400 administrative tasks. It has to
         In addition, the AS/400 will run           a program is run, it is compiled into        be installed on a PC attached to the
     WebLogic from BEA Systems, the first           machine-specific code (and hence will        network, and can then be used to con-
     Web/Java application server to fully           run more slowly). On subsequent oc-          trol all or any of the AS/400s on the
     support all the EJB (Enterprise Java-          casions, that compiled version is run        network in a typical Windows tree
     Beans) APIs, placing it right at the lead-     instead.                                     view format. For example, by expand-
     ing edge of software compatibility -              Thus, unless you delete the pro-          ing the entry for a single AS/400, you
     ahead even of Sun.                             gram template, you can change the            can then look at the various properties
         However, you won’t find the main-          AS/400 technology entirely and your          - file systems, databases, printers, job
     stream databases ported to the                 application will run entirely unmodi-        management, system configuration,

File: T1403.2
                                                   PC Network Advisor                                          Issue 106 (April 1999) Page 10


     security, and users and groups - that      new management feature allows you           The result is that for each additional
     can be managed from the PC.                to build a software package on one          processor you add to the AS/400e (and
         As well as administration, it’s also   central machine and then distribute it      you can have up to 12), you actually
     possible to do performance monitor-        to other AS/400s - a feature that would     benefit by 85-90% of its potential per-
     ing. Not dissimilar in concept to the      be particularly suitable for distribution   formance.
     Windows NT Performance Monitor,            to branch offices. It’s also possible to        Other technology included in the
     this allows you to monitor key indica-     distribute PTFs in that way.                AS/400 is aimed at ensuring reliability
     tors like the percentage CPU utilisation      There’s also a Tivoli agent for the      and availability, and this does seem to
     in a graphical display. You can set        AS/400, so all the facilities available     pay off. IBM’s own experience is that
     thresholds that can trigger applica-       from Management Central are also            since replacing a network of PC servers
     tions to run on either the AS/400 or the   controllable by Tivoli.                     with an AS/400 to run Domino, no
     monitoring PC when they are crossed.                                                   outages at all, as a result of either hard-
     Scheduled jobs can also be run - for       Hardware                                    ware or operating system failure, have
     example, to collect performance infor-                                                 occurred. An independent survey by
     mation for all AS/400s located in the         The AS/400e uses custom versions         IDC of Lotus Domino installations re-
     German offices at 0300 on Wednesday        of the 64-bit PowerPC processor. Dif-       vealed that AS/400 users experienced
     morning.                                   ferent processors are used on different     less than 40 minutes of unscheduled
         Although the graphical display is      models - for example, the top-end sys-      downtime each per year on average,
     useful, it doesn’t provide much detail.    tems employ the PowerPC AS A30,             whereas PC LAN users could expect to
     With release 4.4 of OS/400, detailed       which has a 256-bit data bus (which is      suffer over 13 hours. Perhaps more in-
     information will be available from         how these systems can deliver main-         teresting is that the average number of
     Management Central, enabling it to be      frame performance). Although clock          IT man-hours spent on recovering
     used for things like capacity planning.    speeds may appear low in comparison         from incidents was just 0.9 for AS/400s
     To make life easy, wizards will allow      with Intel-based systems, the size of       but five for PC LANs.
     you to specify the data you want to be     the data bus and other aspects of the           One of the technology features is a
     collected centrally from the AS/400s       system architecture - often using ad-       service processor, which runs even if
     on the network.                            vanced technology from IBM’s re-            the main system crashes or is switched
         Another feature available today        search labs - deliver vastly greater        off, and monitors the system for any
     performs software and hardware in-         performance in server applications.         serious problems such as overheating.
     ventory collection, and can report on         For example, I/O processors are          It can also be used to restart the system
     the level of operating system and all      used to avoid loading the main CPU          in the event of catastrophic failure. The
     applications installed, together with      with I/O tasks. And in the high-end         service processor is normally accessed
     their patch (known as PTF or Program       multiple processor systems, where ex-       via a hardware control panel and asso-
     Temporary Fix) levels. Disk capacity       tremely high performance is desirable       ciated LCD display, but it’s also possi-
     and hardware configuration are also        and cost isn’t so important, a 128-bit      ble to connect it directly to a PC. That
     reported.                                  memory crossbar switch is used to con-      PC can then be accessed remotely - for
         In the desktop world, software dis-    trol access between the different proc-     example, via a dial-in link - allowing
     tribution challenges have been solved      essor and memory cards, rather than a       complete control over the AS/400e
     by technologies such as Novell’s Zen-      single bus. This astonishing quantity of    from anywhere in the world.
     Works. Even though AS/400s are             high-performance hardware is de-                Apart from these special features,
     somewhat bigger than desktop PCs, as       signed to address the problem of con-       the hardware specifications look much
     soon as you have more than one or two      tention that severely limits the            like any other server, with varying
     - and especially if they are spread        scalability of SMP systems that use a       amounts of first and second level cache
     around the world - software installa-      single memory bus, such as the usual        and main memory depending on the
     tion becomes a significant overhead. A     Intel / Windows NT implementations.         model, and different hard drive sizes
                                                                                            and tape drives. Performance may be
                                                                                            different than you are used to, how-
                                                                                            ever, with tape drives offering backup
           “IBM offers a variety of connection                                              speeds of up to 32 GB/hour.

           technologies on the AS/400e range,                                               Networking
            from Twinaxial to Ethernet. In a                                                   IBM offers a variety of connection
                                                                                            technologies on the AS/400e range,
           modern environment, only Ethernet                                                from Twinaxial to Ethernet. In a mod-
                                                                                            ern environment, only Ethernet is
                is likely to be of interest.”                                               likely to be of interest, and to a lesser
                                                                                            extent Token Ring. Twinax is the tech-
                                                                                            nology used by IBM to connect green-

Issue 106 (April 1999) Page 11
                                                PC Network Advisor                                                             File: T1403.3

     screen dumb terminals. The AS/400e           time zone, allowing multinationals to        IPCS). Tape backups will run at the full
     supports TCP/IP, and OS/400 in-              support different countries’ operations      AS/400 speed of up to 32 GB per hour,
     cludes a DHCP server, a DNS server           on the same machine.                         and a very high speed internal TCP/IP
     and an http server. From the general            With Lotus Domino, for example,           link allows fast data transfer between
     TCP/IP networking point of view, it          partitioning can be used to protect line-    the AS/400 and PC server applica-
     can thus be treated much like a Win-         of-business applications such as ERP         tions.
     dows NT, Linux or Unix server.               from Domino partitions, and Domino              The obvious drawback is that the
         Unfortunately, there isn’t yet the       partitions from each other. Although         PC market evolves quickly, and the
     equivalent of NDS for NT for the             downtime may be far less on an               IPCS doesn’t. By using standard PCs,
     AS/400e, but there is a product that         AS/400 than on a PC LAN, Domino              you can rapidly take advantage of new
     helps with integration of an AS/400          can fail, and partitioning will limit the    technologies and levels of perform-
     into a Novell network. OS/400 En-            number of users affected by one parti-       ance when they become available. The
     hanced Integration for Novell Net-           tion failing. Furthermore, the AS/400        IPCS is currently a single-processor de-
     Ware will distribute AS/400 group            features automatic recovery, so a failed     sign, so SMP isn’t an option at all. If
     and user profiles to multiple NDS trees      partition will be restarted without in-      that isn’t an issue, then in theory the
     and even to NetWare 3.12 bindery             tervention.                                  AS/400 can be used purely to consoli-
     services. When AS/400 users change              Partitioning means that where you         date PC servers - with, say, 15 servers
     passwords, the change is propagated          might have considered buying several         and one hot spare - and give better
     to NDS or the bindery, and AS/400            separate AS/400s in order to protect         availability than the equivalent 15 PC
     users are authenticated against the          applications from each other, you can        servers.
     NDS or the bindery.                          buy a much larger machine instead,
         AS/400 users also have access to         with a resultant saving in administra-       Conclusion
     files, directories and printers on Net-      tive costs. An IDC white paper pub-
     Ware servers. To operate OS/400 En-          lished in September 1998 based on a             When deciding on an ERP pack-
     hanced Integration for Novell                survey of 500 commercial sites deter-        aged application, businesses generally
     NetWare, you need to install an NLM          mined that a single large system re-         choose the software first and then the
     on the NetWare servers. Certain Net-         placing five smaller ones resulted in a      most appropriate platform. In such cir-
     Ware administrative tasks, such as           15% annual cost reduction per user.          cumstances, where decisions are
     user profile administration and                                                           driven by considerations of total cost
     backup, can be carried out by the            IPCS                                         of ownership, the security, reliability
     AS/400 operator.                                                                          and manageability of the AS/400 plat-
         Similar facilities are also available       Recognising that users still want to      form make it definitely worth consid-
     for Windows NT, but only where Win-          run PC operating systems such as             eration.
     dows NT is installed on the optional         Novell NetWare and Windows NT,                  Already a true 64-bit platform, the
     Integrated PC Server (IPCS).                 IBM manufactures an IPCS for the             availability of both high-performance
                                                  AS/400. Basically, this is a PC on a         Java and the WebLogic application
     Partitions                                   plug-in card, and you can put up to 16       server from BEA Systems makes the
                                                  in a single AS/400. Given that PCs           AS/400 one of the most advanced
         Enterprise servers generally allow       aren’t exactly expensive, this may           computing platforms today, yet IBM’s
     some form of partitioning - indeed,          seem like a silly thing to do. But be-       efforts on the cost of ownership front
     Gregory F Pfister said in In Search Of       cause the IPCS shares a lot of the supe-     mean that it requires less effort to man-
     Clusters, “Any type of server system, if     rior AS/400 infrastructure and               age than an equivalent network of PC
     it is sufficiently large, eventually be-     technology (it uses the AS/400 disk          servers.
     comes partitionable by customer de-          and tape, for example), it benefits from
     mand” - and the AS/400 is no                 greatly enhanced availability. You can
     exception. Partitioning is a mechanism       even designate one of the IPCS cards
     whereby several different instances of       as a hot spare, and switch over to it in                                   PCNA
     the operating system and application         the event of failure of one of the others.
     can exist on one system.                        Implementing PC servers on IPCS
         Although operating system outages        cards will reduce the total support
     are unlikely, they are not impossible,       costs of a mixed AS/400-PC environ-
     and application failures - while they        ment, and the total number of staff
     may be far less frequent than on a PC        required. For example, if a branch of-                 The Author
     LAN platform - do certainly happen.          fice has an AS/400 plus IPCS, then the
     With partitions, you effectively have        hard drive on the IPCS can to all intents      Andrew Ward is a freelance jour-
     several different machines that are          and purposes be made larger by an              nalist and writer who specialises
     protected from each other. Further-          operator working at the AS/400 at cen-         in business and technology sub-
     more, each partition can have its own        tral office (by remotely increasing the        jects. He can be contacted as an-
     attributes, including language and           amount of AS/400 disk allocated to the

File: T1403.4
                                                 PC Network Advisor                                           Issue 106 (April 1999) Page 12
This article was reprinted from PC Network Advisor with the
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