Let’s take a closer look at Linux on the mainframe. A large percentage of users are running pilot projects on mainframe Linux, and a significant number of users in the telecommunications and financial spaces are running production applications such as “billing inquiry” on mainframe Linux. Deployment and management of large numbers of virtual Linux servers can pose a management problem and open security risks. Managing these Linux environments, therefore, is critical.
At its December 2002 Data Center Conference, Gartner confirmed that interest in server consolidation is still high. A survey of the 950 attendees showed that about 16 percent are using Linux as a method for server consolidation.
The popularity of Linux has actually helped to drive mainframe shipments, accounting for 15 percent of the new MIPS shipped in 2001, and 20 percent in 2002, by Gartner’s estimation. Gartner says that more than 200 IBM mainframe customers have deployed at least one Linux application on mainframe systems in production environments. Another 400 are in the process of implementing Linux applications on the mainframe, or are at least evaluating doing so.
The strategic importance of mainframe Linux will become increasingly evident over the next 18 to 24 months. The platform’s unmatched capability to host thousands of Linux-based virtual servers on a single machine will continue to make it a preferred physical server consolidation vehicle. More important is the platform’s ability to integrate state-of-the-art business application solutions with legacy business transactions and data hosted by traditional mainframe operating system environments running on the same physical server. This, in effect, bridges the gap between the old and new worlds, leveraging the best of both.
Use of the mainframe exclusive HiperSockets capability (an in-memory virtual network) will become pervasive as more businesses discover they can easily connect the latest off-the-shelf applications running under Linux with highly reliable and scalable database systems hosted by z/OS on the same physical box. The near-zero latency of the virtual communication path between the two worlds allows customers to leverage the unique capabilities of both environments without suffering any performance penalty. No other server platform solution provides this capability!
Virtualization is a prerequisite for the deployment of a dynamic, self-managing computing infrastructure. The combination of Linux and time-tested mainframe software virtualization capabilities make it possible to build a computing infrastructure that can quickly adapt to changing workload conditions. For example, in the not too distant future, customers will routinely employ VM to dynamically provision and repurpose virtual Linux servers to create operating environments that are responsive to business requirements. The relatively small footprint of mainframe Linux (as compared to other mainframe application- hosting environments) makes it ideal for this purpose.
Finally, it is no secret that most new applications are being written based on open standards. Technologies such as Java are being employed to provide application portability. However, making high-usage middleware functions such as database systems portable—a requirement for managing software development and acquisition costs—requires much more than a programming language. Providing portability for most performance- sensitive middleware requires that the software be written to a standardized set of operating system interfaces. Linux is rapidly becoming the de facto standard for middleware deployment. Mission-critical, Linux-based business applications deployed on key middleware infrastructures such as WebSphere will, in many cases, need to scale beyond the I/O bandwidth limitations of traditional distributed servers. Mainframe Linux will satisfy the resource requirements of these high-end applications.
In addition to managing Linux from an application perspective, users also may need to manage the physical and logical environment in which the Linux application resides—VM and z/OS. Many of these applications are accessing data running in DB2 and IMS under z/OS. To address these various environments, it is important for users to manage from this holistic perspective.
MAKING THE MAINFRAME ENVIRONMENT EASIER TO MANAGE
A preponderance of the evidence examined reveals continuing growth in mission-critical mainframe applications. Given this continued growth, how do we make this mainframe environment easier to manage? Now, more than ever, there is a need to maintain highly efficient mainframe applications by implementing an application quality management process. IT executives often face the conflicting goals of reducing application development and deployment costs while increasing quality and customer satisfaction. Meanwhile, application developers focus on functionality and often do not have time to consider application performance. When new and modified applications are deployed, the IT staff is pressured to keep the applications and system running at required service levels while containing costs.