In-Depth
Behind IBM's Bifurcated Hybrid Computing Strategy
For most organizations, choosing between Big Blue's two hybrid computing visions is simple, but what about shops that need both? That's where it gets tricky.
When IBM Corp. unveiled its new PureSystems hybrid computing push back in early April, it didn't announce a Big Iron component.
PureSystems supports an array of proprietary and open operating environments, including AIX, System i, Linux, and Windows, but it doesn't support z/OS or other IBM mainframe operating environments, for that matter, such as z/VM and VSE.
While IBM pitches PureSystems as a less-costly alternative to almost any existing computing infrastructure, it carves out an exception for the mainframe for the simple reason that Big Iron is (currently, and for the immediate future) distinctly separated from the PureSystems model. The same is true for hybrid computing on System z, which -- at this point -- doesn't involve IBM's System i platform, either natively (i.e., running in some context on the mainframe CMOS) or adjacently, running in the context of Big Blue's zEnterprise BladeCenter Extension (zBX).
Although it's possible to connect the separate hybrid computing worlds of PureSystems and zEnterprise, IBM doesn't yet offer a complete, all-in-one package for hybrid computing. "Integration" between the PureSystems and zEnterprise hybrid computing environments takes the form of Ethernet connectivity and Tivoli management software.
What's a would-be hybrid computing adopter to do?
Industry veteran Alan Radding, who regularly writes about mainframes and enterprise technology on his Dancing Dinosaur blog helpfully breaks down the costs of both hybrid computing visions.
If cost is the primary criterion, Radding writes, then PureSystems probably has the edge. "PureSystems probably will cost less, how much less depends on how it is configured," he writes, citing a starting price (for entry-level PureFlex) of $156,000; a mid-level cost of $217,000 for PureFlex Standard; and a cool $312,000 for PureFlex Enterprise. (IBM positions the latter as a platform for scalable cloud deployments.)
These prices don't include the cost of OS and hypervisor software, Radding notes.
"The zEnterprise option will cost more but maybe not all that much more depending on how you configure it, [on] whether you can take advantage of the System z Solution Edition packages, and [on] how well you negotiate," he points out, citing a $75,000 asking price for Big Blue's entry-level zEnterprise/zBX hybrid computing package, which is based on IBM's very affordable zEnterprise 114 mainframe.
"[E]xpect to pay more [for this entry level offering] once it is configured," Radding continues, putting the cost for a zBX at "about $200k or more ... depending on the type and number of blades, plus whatever you need for storage."
In the final analysis, however, cost is beside the point. In the overwhelming majority of cases, after all, shops that have mainframe assets will opt for hybrid computing with System z. Shops that don't, won't. System i shops -- like their System z counterparts -- will go with the vision that supports their platform. For i-centric organizations, that's PureSystems.
"Obviously, if you need z/OS, you go with the zEnterprise. It provides the optimum platform for enterprise computing with its extreme scalability and leading security and resiliency. It supports tens of thousands of users while new offerings expand the z role in BI and real time analytics, especially if much of the data reside on the z," Radding writes. "If you must include i you go with the PureFlex, or if you find you have a hybrid workload but don't require the governance and tight integration with the z, you can choose IBM PureFlex and connect it to the zEnterprise via your existing network. Tivoli products can provide the integration of business processes."
What about organizations that need both or that need a one-stop shop for hybrid computing that addresses all of their platform needs, from System i to zEnterprise?
That's where it gets tricky. For starters, it isn't clear that IBM needs to flesh out either of its hybrid computing visions, either by introducing a System i-specific zBX offering for zEnterprise or by creating a special mainframe package for PureSystems. That's because it isn't about the hardware. The key selling point of PureSystems is its unified, one-stop management experience, which is delivered via the Flex System Manager console. IBM offers a similar capability on the Big Iron side with its zEnterprise BladeCenter Extender (zBX) and Unified Resource Manager (URM).
PureSystems and the zBX/URM-enabled mainframe could be considered two sides of the same coin: both aim to support a highly resilient, highly flexible, highly automated, and highly manageable hybrid computing experience. PureSystems is the open systems counterweight to zBX/URM. From this perspective, an i-based zBX offering is more easily conceivable -- in the short term -- than is the development of a special mainframe package for PureSystems. The latter would require that Flex first be fleshed out with mainframe support.
If IBM's going to do that, couldn't it extend Flex to manage zEnterprise/zBX hybrid environments, too? That might not be so easy. At this point, IBM doesn't offer very many ready answers. "Right now the wrinkle in the hybrid computing management efficiency story comes from organizations that want both the zEnterprise and PureSystems. This would not be an odd pairing at all, but it will require two different management tools, Flex System Manager for the PureSystems environment and the Unified Resource Manager for the zEnterprise-zBX," Radding notes. "At a recent briefing an IBM manager noted that discussions already were underway to bring the two management schemes together although when and how that actually might happen he couldn't say. Let's hope it is sooner rather than later."