On October 12, 2011, IBM announced the z/VM version 6.2. This newest release introduced single system image (SSI) and live guest relocation (LGR), a first for the mainframe. SSI is a separately orderable priced feature of the z/VM version 6.2. This new version of z/VM introduces multisystem clustering technology that allows up to 4 z/VM instances in a single system image cluster. This is important because it offers clients an attractive alternative to vertical growth by adding new z/VM systems. In the past, this capability required duplicate efforts to install, maintain, and manage each system. With SSI, these duplicate efforts are reduced or eliminated.
In the IBM Redbooks publication, An introduction to z/VM single system image (SSI) and life guest relocation (LGR), SG24-8006, the reader will learn about the business benefits of SSI and LGR. They will understand important concepts and planning and finally, they'll step through implementation and practical approaches.
There is an ever-increasing demand for IT resources and tighter budgets. Smarter computing addresses this challenge through IT transformation. Virtualization is a key element of transformation that helps reduce sprawling IT landscapes. Virtualization helps provide flexibility to meet user demands for security, availability, scalability and manageability of IBM System z.
But what are the business benefits of using this new z/VM?
- When SSI is used to create clusters, each member can be serviced managed and administered as though they are one integrated system. Coordinating the joining and leaving of members to and from the cluster while maintaining a common view of cluster members and resource states and negotiating access to shared cluster resources are all done seamlessly. This avoids virtual machine sprawl challenges. These challenges include the creation of uncontrolled numbers of virtual machines that IT managers don't know about, whether they are up or down and whether they are secure.
- sharing all system resources with high levels of resource utilization is extended with z/VM V6 .2. Resources that are used by the z/VM hypervisors and the virtual machines are shared. The shared resources are managed as a single resource pool and provide a more manageable infrastructure. These resources include the user directories, minidisks, spoke files, network device Mac addresses and security definitions. Sharing resources among members improves the integrity and performance of the system. Through resource sharing, virtual servers have access to the same devices and networks regardless of which z/VM member they are logged on to within the SSI cluster.
- Sharing resources allows service to be rolled out to each member of the cluster on individual schedules, avoiding an outage for the entire cluster.
- With SSI, there is concurrent support for virtual machines running separate operating systems and a secure isolated environment.
Want to learn more about using z/VM 6.2 with SSI and LGR? Two very good IBM Redbooks publications available today are: