2.5    Virtualization

You’ve most likely heard about how virtualizing your IT environment can save money by cutting costs and increasing efficiency. In this section we’ll discuss what virtualization is, how it applies to SAP HANA, and the different virtualization vendors currently certified by SAP.

2.5.1    What Is Virtualization?

You might be asking: What is virtualization? Virtualization is the process of creating a software-based representation of a computer rather than a physical one. Virtualization can apply to applications, servers, storage, and networks and is the most effective way to reduce IT expenses while boosting efficiency and agility for all business applications.

Is virtualization the same as cloud computing? In a word, no, although cloud computing uses virtualization technology. In cloud computing, hardware is owned by a company that sells virtual machines (VMs). A VM is an isolated software container with an operating system and application inside.

Organizations are faced with the limitations of today’s servers, which are designed to run only one operating system and application at a time. This limitation causes organizations to deploy many servers that only operate at 5 to 10 percent capacity, which is extremely inefficient by any standard.

Virtualization allows for multiple operating systems to be installed on one server with the use of a hypervisor. The hypervisor is a thin layer of software installed directly on the server to simulate the existence of hardware. The server is now referred to as a host, and multiple VMs can then be installed on top of the hypervisor. Figure 2.10 illustrates how the hardware, hypervisor, and VMs work.

Each VM is completely independent from the host and other VMs. For example, six VMs could be on one host, with one running SUSE Linux, two running Red Hat Linux, two running Windows Server 2012 R2, and one running Windows 10. Each VM has its own IP address and can be moved to any other host running the same hypervisor.

High-Level Virtualization View

Figure 2.10    High-Level Virtualization View

Now that you have a better understanding of what virtualization is, let’s look at the virtualization options for SAP HANA.

2.5.2    SAP HANA Virtualization

With the release of SAP HANA SPS 05, SAP announced support for VMware’s hypervisor, the first technology supported to partition an SAP HANA server into smaller partitions or VMs. Since then, SAP has expanded its support for running SAP HANA in virtualized and multitenant environments by adding different scenarios and hypervisors.

Cost Control

Deploying SAP HANA in a virtualized environment allows you to control costs and run only the required memory for your system. As your data expands, you can expand within the infrastructure and not be bound to the physical limitations of an appliance. In addition, SAP HANA isn’t tied to a specific server. The VM can be moved to another SAP-certified hardware appliance without losing the license.

High Availability

Many hypervisors, like VMware’s, provide high availability, allowing for VMs to be migrated live to another host and to take snapshots for recovery and complete backup images of the machine. Combined with SAP HANA’s high-availability technology, database snapshots and backups can make your environment virtually bulletproof.

SAP Note 17886655 is the master note for SAP HANA virtualization. This note will be regularly updated with the SAP HANA-supported hypervisors. Currently, VMware, Hitachi LPAR, Huawei, and IBM PowerVM are supported for production environments. KVM and XEN hypervisors may also be used for SAP HANA SPS 11 and later releases for nonproduction uses cases.

Following is a list of the currently-supported hypervisors for SAP HANA:

Note

The SAP HANA system set up needs to be performed by an SAP HANA certified engineer on SAP HANA certified hardware and successfully verified with the SAP HANA hardware configuration check tool (SAP HANA TDI option) SAP Note 1943937. Alternatively, the system can be delivered preconfigured with a hypervisor and the SAP HANA software installed by an SAP HANA hardware partner (SAP HANA appliance option).