Linux on System z Update

It has taken a decade but Linux has finally firmly established itself in the mainframe world. As recently as 2Q 2012, IBM was reporting two-thirds of its top 100 customers had deployed IFLs, the assist processor for running Linux on the mainframe. Overall, one-third of its System z customers have deployed IFLs. Regardless of whether you are running Linux on the z today or not, Linux on z along with Java saved the mainframe from becoming just another niche technology instead of the versatile core enterprise platform it is today.

SUSE Linux Enterprise is the dominant version on Linux on the mainframe.  SUSE now is owned by Attachmate, which says it will runs it as an independent business unit to ensure it continues to focus on the benefits of open source.  SUSE has about 65% of the mainframe Linux market. Ubuntu and Fedora have negligible presence among mainframe Linux.

Red Hat Enterprise Linux (RHEL) holds most of the remainder on the mainframe Linux market.  Red Hat also offers Fedora, another Linux distribution intended primarily for individuals. After making steady inroads into SUSE’s mainframe Linux market share, progress appears to have slowed in recent months. At its annual Red Hat Summit last June the company celebrated crossing the $1 billion annual revenue threshold, a major achievement for any organization but especially for one built around an open source product.  The Red Hat event returns to Boston in 2013, June 11-14.

The Red Hat gathering  focused on the current hot IT issues—cloud, mobility, and cloud storage—but the mainframe was noticeably  absent. There has been some shifting of responsibilities among Red Hat personnel regarding the mainframe, but DancingDinosaur has been told it remains an active initiative. DancingDinosaur believes RHEL on the mainframe can certainly play an integral role in driving RHEL adoption throughout the enterprise, especially as it spreads through IBM’s various hybrid computing and cloud initiatives. And having two active Linux on z providers is good for mainframe computing.

This coming fall marks the first SUSECon event, something SUSE intends to make into an annual event. Planned for Orlando FL, Sept. 18-21, the event already is promoting Doug Balog, general manager, IBM System z, as a keynote. Balog is responsible for IBM’s worldwide System z server business. The conference promises to address enterprise Linux in the data center, cloud technology and infrastructure, and Linux systems management; basically what you’d expect.

In the meantime, SUSE released the second Service Pack for SUSE Linux Enterprise 11, which includes advanced exploitation of the latest IBM zEnterprise hardware, improved systems management, increased performance, and better problem analysis and resolution.  For example, new support for SSD makes it transparent to the DASD device driver, meaning no change required to use SSD

In terms of Linux functionality on the mainframe users see little differentiation between SUSE and RHEL from a product functionality standpoint. Makes sense since both are based on the Linux open source kernel. DancingDinosaur has profiled mainframe shops using each distribution. The choice often comes down to familiarity, services, and vendor attention to the customer. As hybrid computing gains traction among mainframe and Power shops and eventually PureSystems shops, however, the vendor—SUSE or Red Hat—that best addresses these new optimized multi-platform environments may gain an advantage.

For now, distinctions are minimal. A leading insurance company reports that it ended up using both distributions on its mainframe, starting first with Red Hat and then switching to SUSE and, a few years later, switching back to Red Hat.  As the project manager noted: “Either one works fine; you simply have to consider if your company already has a relationship with one of the vendors, your workload requirements, and any cost differences for code and support.” You also need to consider vendor readiness to support future initiatives like cloud, hybrid computing, mobile, and social business.

But changes are coming fast. IBM is inviting the industry to tomorrow’s virtual announcement of what it bills as the next generation zEnterprise system. Check it out.  DancingDinosaur will cover it in the next post.

zBX and the Next IBM Hypervisor

Even before the zEnterprise/zBX was introduced, most mainframe data centers were multi-platform, multi-OS shops. IBM had z/VM and Power VM as hypervisors for System z and Power systems, but in the x86 world VMware ESX ruled, followed by Microsoft’s Hyper-V.

So, it was significant when IBM announced in early May that it and Red Hat, an open source technology leader, are working together to make products built around the Kernel-based Virtual Machine (KVM) open source technology for the enterprise. Jean Staten Healy, IBM’s Director of Worldwide Cross-IBM Linux, told IT industry analysts that the two companies together are committed to driving adoption of the open source virtualization technology through joint development projects and enablement of the KVM ecosystem. DancingDinosaur touched on aspects of this several weeks ago, here.

Differentiating the KVM approach from those taken by the current x86 virtualization leaders is open source technology. An open source approach to virtualization, Healy noted, lowers costs, enables greater interoperability, and increases options through multiple sources.

The KVM open source hypervisor allows a business to create multiple virtual versions of Linux and Windows environments on the same server. Companies can take KVM-based products and combine them with comprehensive management capabilities to create highly scalable and reliable, fully cloud-capable systems that enable the consolidation and sharing of massive numbers of virtualized applications and servers.

Red Hat Enterprise Virtualization (RHEV), for example, was designed for such large scale datacenter virtualization by combining its centralized virtualization management capabilities and advanced features with the KVM hypervisor. BottomlineIT looked at the Red Hat open source approach to virtualization a few weeks ago.

The open source approach to virtualization is starting to gain traction. To that end Red Hat, IBM, BMC, HP, Intel, and others joined to form the Open Virtualization Alliance. Its goal is to facilitate  the adoption of open virtualization technologies, especially KVM. It intends do this by promoting examples of customer successes, encourage interoperability, and accelerate the expansion of the ecosystem of third party solutions around KVM. A growing and robust ecosystem around KVM is essential if the open source hypervisor is to effectively rival VMware and Microsoft.

IBM’s interest in KVM also raises the question of which hypervisor—z/VM, PowerVM, RHEL in the form of RHEV with KVM, or something else—will become the preferred hypervisor for the zBX, especially when organizations start running Power and System x blades and mixed workloads. In an interview with the Register a few months back, Jeff Frey, an IBM Fellow and contributor the zEnterprise/zBX laid out the hypervisor challenge with the zBX:

• zEnterprise—IBM’s own Processor Resource/System Manage (PR/SM) type 1 hypervisor and its related z/VM operating system (which can function as a type 2 hypervisor) will continue to direct resource activity on the zEnterprise 196.
• PowerVM—a hypervisor that divides Power systems and blades into logical slices to virtualize I/O as well as to support AIX continues with IBM’s Power platforms.
• IBM’s System x—Xeon blades will use a version of KVM that works with System z firmware.

The hypervisors on the Power and Xeon blades are treated like other system firmware on the mainframe. Not only do PR/SM, PowerVM, and RHEV get treated like firmware on the z but are linked back to the zEnterprise and the Unified Resource Manager via a built-in Gigabit Ethernet network implemented in a switch in the z.

Result: The switch hooks into the Advanced Management Module in the BladeCenter chassis, while the Unified Resource Manager uses SNMP to manage the BladeCenter and zBX hardware and has hooks into the PowerVM and KVM hypervisors to manage virtual machine partitions on the Power and Xeon blades.

For IBM the KVM technology is particularly well suited to address cloud challenges. It provides a predictable and familiar environment, auditable security compliance, and an open source licensing model that keeps costs down while requiring no additional skills. This makes it particularly cost-effective for large-scale cloud use, public or private, which is where IBM sees all this virtualization taking enterprises.