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iSeries rises to conflicting demands

IBM's iSeries will never be IBM's most exciting range of servers, but it is destined for great things, according to one of its architects

While other systems hit the headlines, IBM's iSeries, formerly known as the AS/400, just carries on doing what it does best. Segment manager for enterprise technologies on the iSeries, Amit Dave, spoke to ZDNet UK about the future for IBM's most business-like servers. The iSeries is benefiting from IBM's efforts to share technologies across all its servers, and Dave has been in charge of this for the iSeries, bringing eLiza to the system, along with logical partitions, storage networks and grid computing. Yet while IBM servers become more alike, Dave believes iSeries is going to maintain its own identity. He disclosed his ideas to us. Technologies spreading
The mainframe division is the source of most of the technology which IBM is sharing across its servers. This policy was instituted by former IBM president, Lou Gerstner, and operates on every level. In manufacturing, systems are made from common parts as far as possible. "Eight years ago, the machines did not even use the same power supplies," said Dave. "It doesn't make sense for the company to have four production lines and not share a bag of parts. Under Gerstner, that mentality got crushed." Now, IBM production lines can change easily between making mainframes and other servers, since so many of the parts are common. The sharing of software is more exciting though. The biggest developments in iSeries software have been items brought across from the mainframe world, but the iSeries' own developers have been keeping their end up. The most recent big iSeries software announcement, version 5 release 2 (V5R2) of the OS/400 operating system, was launched in April. "This was the largest release to come out of Rochester [Minnesota, the home of the iSeries]," said Dave, "both in the number of lines of code and the richness of features." The new release is the foundation of future efforts to enhance the middleware on the iSeries, he said. In the future, "we want to be the flexible server of choice," he said. Among the additions to OS/400 was single sign-on to applications on multiple iSeries servers. This is Enterprise Identity Mapping (EIM), an eLiza initiative, based on the widely used Kerberos authentication system and the directory standard LDAP. As an eLiza project, EIM is going to show up on other systems. LPAR, the key to consolidation
The release extended the use of logical partitioning (LPAR) in iSeries. "Years ago, you would not have been allowed to take LPAR from the 390 [mainframe] to the iSeries," said Dave. "But we did it." Rochester is leading development on LPAR beyond the mainframe, according to Dave. "Technology exchange is happening, and we are seeing the rewards." LPAR lets the user run multiple operating systems, or multiple versions of the same operating system in separate partitions on one machine. It is fundamental to the future of the iSeries, said Dave. For one thing, this allows consolidation, letting users run multiple operating systems without having to dedicate a server to any of them. This is particularly important if one operating system is required for some non-critical task which runs at intervals, such as a month-end accounts run. Potentially, it could also help if the company has an application which needs Oracle instead of the iSeries' native database, DB2. It is also useful within one operating system, if the user has applications which only work on certain versions. Older versions of the OS can be kept going while applications are migrated, and newer versions can be tried out without risking the whole system. However, so far the only other operating system to run in an LPAR partition is Linux. Despite leaks that implied that V5R2 would support IBM's own Unix version, AIX, in LPAR, all that came out was a "statement of direction" (SOD) to say it would happen. These statements are IBM's way of telling you something is coming in about 18 months time, so users must wait till 2004 for AIX partitions on their iSeries systems. Another slight disappointment was IBM's failure to allow 255 partitions. This, again is promised for the future. LPAR first arrived on the iSeries in 1999, but at that stage it was static, with partitions set up "in stone", and only on certain systems. Dynamic LPAR, which lets the administrator tune the amount of resources given to each partition, arrived in May 2001. "There has been tremendous uptake of LPAR," said Dave. " We want 100% deployment, and it is now 45%." This rate of use is impressive, given that the feature has only properly been available for a year, and requires iSeries users (renowned for their conservatism) to move to release 5 of the operating system. "We have yet to see anyone get upset by it." Elsewhere in IBM's range, the AIX-based pSeries also has LPAR. Both iSeries and pSeries have the same Hypervisor tool to manage the partitions. The pSeries and iSeries are both mid-range systems, supporting from tens to thousands of users. As long as they have both existed, commentators have asked whether one will eventually win out over the other. IBM's answer has always remained the same, that both are aimed at different markets. But surely the cross-fertilisation of technologies will erode the differences? Dave does not think so: "They are totally different in nature," he said. "People used to say that the mainframe would go away, but it didn't." The two systems now have virtually the same parts, so the difference is not hardware, but software and operating system, he admits: "We will carry on seeing offerings from OS/400 and AIX, even though the hardware will converge. We have removed the focus on hardware, and are looking to the middleware." However, he does say that in hardware the two systems have a totally different I/O path, and this will remain different: "The iSeries has always had distributed I/O and this will evolve." IBM has argued that the iSeries has a lower cost of ownership than other systems because it is a plug-and-play systems which is easier to administer. This must be weakened by moves to simplify management on all systems. iSeries and pSeries will have a common interface for management, said Dave, so that administrators will only need to be trained once. Offering the same management tools on both systems has become easier, because iSeries does in fact have an AIX interface. PASE (portable application solution environment) allows AIX applications to run natively on iSeries, but doesn't support the whole AIX environment (so it is no substitute for the promised LPAR implementation). "We did not rewrite Tivoli for iSeries -- we just used PASE to bring in," said Dave. "We do this more and more to bring middleware across." PASE itself is expected to be developed further in future versions of the iSeries software. Despite Dave's insistence, the delay to the AIX LPAR looks very much like an effort to keep a distinction between the two. There is no doubt that allowing technology to transfer between the different server lines has revitalised the iSeries, allowing it to continue where other suppliers' proprietary mid-range systems died years ago. But the eventual result, of a company selling the same mid-range machine in two flavours, will be a severe test of IBM's marketing brains. The heart of the iSeries
According to Dave, the iSeries value proposition is that it is highly integrated, while the pSeries is an "open systems" platform which allows users to run different programs from different sources. Even when the hardware is completely identical (the iSeries has run on the same Power processors as the pSeries for several years) and the software is virtually the same. The iSeries masks the complexities of set-up and is designed for a Big-Blue only setup. Traditional IT managers do not want this -- "they say it will put them out of a job," said Dave. But other people like it. He describes an iSeries user -- a Korean gynaecologist who also owns the hospital where he works, and is also the chief information officer (CIO). Without needing to know much about the system, he has a high availability, multi-user business system, run by ordinary hospital staff, said Dave. The rarity of iSeries skills among specialist medical staff may, perhaps, be indicated by the fact that, according to Google, this very page is the first on the Net to include the words "iSeries" and "gynaecologist". Users like this are happy to run IBM's Lotus Notes or Domino collaboration software which, Dave pointed out, runs natively and much faster on the iSeries. "The iSeries is the second favourite platform for running Domino [after Microsoft's NT/2000 platform]," ignoring the fact that Domino itself comes a poor second to Microsoft's Exchange. The fact that more users run it on Microsoft servers is not such good news surely?. Dave leaves the iSeries track for a moment to assure us that "many users will replace Exchange with Domino servers, while keeping Outlook on their desktop." One role suggested for iSeries is sitting behind and supporting Windows systems. For many people "highly integrated" means "proprietary", and the word seems to sting Dave -- needlessly so, because the typical iSeries user has no objection to using a proprietary system. He or she could not care less about open systems; they just want a machine that carries on working. Dave admitted the system is proprietary, but pointed out that it allows IBM to do things like dramatically changing the operating system if required. But it is also open in several important ways. "But are we open and do we adhere to standards in the industry? Yes. Are we open to new technologies? Yes." To illustrate this kind of openness, he pointed to the availability of the popular Apache web server on iSeries, as well as Java and Linux. In fact, he argued that iSeries' proprietary architecture actually makes it a better Java platform. "Java is integrated better into the iSeries than on the pSeries. We have put Java into the microcode." While the open systems demands on the pSeries require it to run Java in a separate layer, iSeries can hide it in the silicon itself, he said. Surviving in the market
While a small fraction of the size of the Windows server market, the iSeries seems healthy. There are 750,000 iSeries machines out there, according to Dave. Each one supports from 20 to 4000 users, so there are tens of millions of users on the system. The machine's competitors vary from industry to industry, said Dave, including Microsoft NT, to Sun, HP and Compaq. "Others don't have the same commitment to focus on TCO," he said. "Feeds and speeds don't excite us - we talk about solutions, while Sun and HP talk about hardware." One source of converts to iSeries might be users stranded on other vendors' erstwhile proprietary mid-range systems, such as the HP3000. These systems, if they are supported at all, tend not to have newer technologies such as Java and web services, and vendors are usually making every effort to move users onto their Unix systems. iSeries may be able to offer this kind of user something close to what they are used to, said Dave. But the touted "ease of use" benefit may be another distinction which is being eroded. Initiatives such as HP's Utility Data Center (UDC) which aims to offer scalable processing and storage on demand may eventually provide something as easy as iSeries, without the downside of proprietary hardware. Here, iSeries has to at least nod to the newer developments, in everything from storage to grid computing. "How do we participate in a SAN environment, while continuing with what we already have been doing in direct attached storage?" mused Dave. "We are looking at ways to continue offering customers a choice." iSeries' involvement in the Grid computing initiative is serious, with machines participating in IBM's Blue Grid test bed. It will be in delivered products, once the standard OGSA (Open Grid Services Architecture) interface is implemented, he said. So it looks like IBM's iSeries team will keep on working at conflicting demands: advanced enough technology, which is nevertheless proven and easy to use; systems which are similar enough to other IBM servers, yet distinctive enough to justify their existence.
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