Companies Recast Platforms for Workload Consolidations

Part 1: The price might be right: IBM's zSeries and iSeries systems facilitate potentially cost-saving server consolidation options

At a time when any enterprise vendor worth its salt is pushing a server consolidation strategy, a number of companies with strong enterprise computing pedigrees—Hewlett-Packard Co. (HP), IBM Corp. and Unisys Corp.—market server consolidation solutions that stand out from the pack.

To a large extent, that’s because all three vendors have undertaken to recast their most scalable and reliable computing platforms—mainframes, minicomputers and high-performance servers—as suitable platforms for the consolidation of Windows, Linux and Unix workloads.

IBM, for example, supports Linux workloads on its S/390 and zSeries mainframes, along with Linux, Windows and even some Unix workloads on its endlessly adaptable iSeries minicomputers. Unisys, for its part, supports traditional mainframe workloads, along with Windows and Unix server partitions, on its ClearPath Plus and ES7000 systems. Starting in 2003, HP will simultaneously support HP-UX, Windows and Linux on its high-end 64-way SuperDome servers.

For the next three issues we'll examine the consolidation strategies of these Big Three systems vendors. We begin with IBM.


In 1999, IBM gave its customers the option to run Linux images on their S/390 mainframes. Since that time, Big Blue has introduced a new version of its mainframe operating environment, z/OS, and also delivered a so-called “baby mainframe”—the z800—that the company is marketing to new and existing customers as a server and workload consolidation platform.

In tandem with the release of the baby z800, IBM also introduced a stripped-down version of its z/OS operating system—z/OS.e—designed to make it easier and cheaper to implement the z800 in server consolidation efforts.

It’s a popular misconception that Linux on the mainframe is a free proposition. To be sure, shops can deploy as many as 15 Linux logical partitions (LPAR) on their mainframes without forking over any additional money to IBM. If they want to put more than 15 Linux images up on an S/390 or zSeries system, however—and the vast majority of consolidation efforts will most likely involve more than 15 servers—they’ve got to license IBM’s Virtual Machine (VM) operating system. Because VM (z/VM on zSeries hardware) sells for about $45,000—and comes bundled with an attendant annual maintenance charge of $11,000—existing mainframe shops probably aren’t going to do this unless they’re serious about Big Iron Linux.

Moreover, mainframe customers must license a copy of VM or z/VM for each of their mainframe processors. In this arrangement, it could cost companies $560,000 to license z/VM for a ten-way z900 system.

IBM offers another solution—its Integrated Facility for Linux (IFL). According to John Phelps, vice president and research director of servers and storage with consultancy Gartner Inc., IFL costs between $125,000 and $200,000. For large-scale efforts in which an organization plans to consolidate the workloads of thousands of Linux servers onto mainframe hardware, Phelps says IFL is a bargain. “[Big Iron Linux has] never been portrayed as free. [Organizations] should do a TCO comparison, and there are a number of cases where it works out very well.”

Not surprisingly, says Lionel Dyck, a systems programmer with a large healthcare provider based in California, it’s usually impractical to acquire an IFL for anything less than a full-scale Linux server consolidation effort.

"It’s not cost-effective to run a single Linux server on an IFL," he says, noting that his company is currently in the midst of a proof-of-concept test involving Linux server consolidation on a mainframe IFL. “[We plan to consolidate] for cost savings, along with reducing the time from server request to server deploy … from months to minutes."

While it doesn’t make sense for every server consolidation scenario—there’s no facility to host Unix or Windows servers on S/390 or zSeries LPARs, for example—IBM’s mainframe platforms do provide a compelling foundation for large Linux consolidation projects. Moreover, says Mary Moore, zSeries and z/OS marketing manager with Big Blue, putting Linux on an LPAR is the easiest way to Web-enable a mainframe environment. “They can either consolidate with Linux on the mainframe, or if they need the z/OS qualities and service, then they can take critical apps to z/OS, and get things like WebSphere, when you want the most robust environment for their Web.”

The result, analysts say, has been a number of new customer wins for zSeries.

“The z800 started shipping at the end of March, [and] IBM [says] they’re shipping close to 100 z800s per month right now, which is a reasonably good … ship rate for those things,” says David Mastrobattista, a senior analyst with Giga Information Group Inc. “Those machines are typically going into shops that … never had a mainframe before, and they’re intrigued with zSeries Linux.”

AS/400 – iSeries

IBM’s iSeries minicomputers provide its customers with perhaps the best overall platform for server consolidation.

To begin with, iSeries runs IBM’s rock-solid OS/400 operating system, which rivals its bigger mainframe brethren in terms of availability and security. OS/400 may be stodgy and un-sexy, but over the years more than 25,000 applications have been written for it.

In addition to the vaunted OS/400 operating environment, IBM also lets its customers run Linux natively on top of iSeries. Big Blue’s top-of-the-line iSeries 890 server can support as many as 31 Linux LPARs. To be sure, that’s a far cry from the hundreds or thousands of Linux images that customers can run on S/390 or zSeries hardware, but—for OS/400 shops that have several dozen Linux servers sitting around—their iSeries hardware can nevertheless function as a bona-fide workload consolidation platform.

According to Tony Madden, vice president of sales for the IBM business unit of Avnet Hall-Mark, a major IBM VAR and Big Blue’s largest iSeries reseller, that’s a possibility that many iSeries shops are exploring. “What we do see is a huge amount of interest in server consolidation, like [on the] zSeries. iSeries benefits from [interest in server consolidation]. It’s a logical consolidation platform because of all of the options that IBM gives customers, and lots of [customers] are taking advantage of [its support for] Linux, Windows and even Unix.”

Ian Jarman, IBM’s iSeries product manager, says that iSeries’ strengths as a server consolidation platform aren’t limited specifically to Linux. Since 1996, he points out, IBM has made it possible for iSeries boxes to simultaneously run Windows applications, first by virtue of the Integrated PC Server (IPCS) for Windows. Big Blue later rechristened IPCS the Integrated Netfinity Server (INS).

In its current incarnation, Jarman says, IBM supports Windows on iSeries by means of its Integrated xSeries Server (IXS), which—in tandem with enhancements to version 5, release 1 (V5R1) of the OS/400 operating system that make it possible to connect multiple IXS and xSeries 350 servers—kicks iSeries’ Windows consolidation story up several notches.

IXS exploits an Intel Pentium III microprocessor and is available in 700-MHz, 850-MHz and 1-GHz speeds. It can support a maximum of 4 GB of RAM.

IXS support varies across the iSeries product line. The low-end iSeries model 270, for example, supports a maximum of three IXS servers. The high-end model 890 supports as many as 32 IXS servers. Regardless of which iSeries model a shop runs, it will have to acquire additional expansion towers or standalone xSeries 350 servers if it plans to undertake a large Windows 2000 consolidation effort. That’s because the iSeries model 890 won’t support more than two IXS servers in its main chassis.

For this reason, IBM offers iSeries customers an option—the Integrated xSeries Adapter (IXA)—to connect IXS expansion towers or standalone xSeries servers to iSeries by means of the latter’s 1 Gbps High Speed Link (HSL) bus. IXA is supported in OS/400 V5R1 and supports as many as 32 direct-attached Windows 2000 Server and Windows 2000 Advanced Server IXS or standalone xSeries 350 servers. Customers can even purchase new xSeries 350 hardware (sans RAID controllers and storage), install IXA, and connect to the iSeries by means of HSL.

The advantage is that the consolidated IXS servers—which are recognized by iSeries as a storage area network (SAN)—have access to the latter’s tape, database and Direct Access Storage Device (DASD) resources. In this configuration, it’s also possible to use IBM’s Operations Manager software to manage the consolidated Windows 2000 systems.

Although he stops short of offering any hard numbers, Avnet Hall-Mark’s Madden says that a lot of his company’s customers have expressed interest in, or are actually deploying solutions based on, iSeries’ IXS. “We actually … see a pretty high-level of interest [in IXS], because of our iSeries base. A lot of these [customers] have Windows in their environments, after all.”

As if that’s not enough, IBM offers the Portable Applications Solutions Environment (PASE) for iSeries, which enables customers to port AIX applications to run on iSeries. While PASE doesn’t emulate an operating system environment or hardware architecture, it does make it possible to consolidate AIX applications on an iSeries minicomputer.

Next week: Unisys.