"High Availability for KVM on z Systems" white paper
KVM for IBM z Systems hosts Linux on z Systems guest virtual machines while benefiting from the high reliability, availability and serviceability characteristics of the z Systems hardware. The KVM for IBM z offering is optimized for z Systems architecture and provides standard Linux and KVM interfaces for operational control of the environment, as well as supporting OpenStack interfaces for virtualization management. This white paper focuses on considerations for setting up a highly-available KVM for IBM z Systems environment hosting your business applications. With IBM’s investments in z Systems reliability, availability and serviceability, z Systems is an excellent platform to host a High Availability (HA) KVM for IBM z Systems environment.
KVM for IBM z Systems leverages Linux components to support hundreds of guest operating systems in each z Systems partition. The components include the KVM kernel module, a guest implementation (via QEMU) and libvirt remote virtualization management. At the same time, availability functions developed specifically for Linux on z are utilized, such as dynamic I/O reconfiguration.
With an awareness of the Linux components that support KVM, the system administrator can configure an environment that takes advantage of the high levels of hardware, firmware and functional redundancy, even when configured to run across multiple partitions (each hosting a KVM hypervisor) in a single physical server! Middleware such as Websphere Application Server Network Deployment and DB2 HADR have built-in clustering technology that enables cluster members to span guests and operate in either an active-active or active-standby fashion. Furthermore, OpenStack can be configured to spread guest images across z Systems partitions, viewing each partition as a separate hypervisor.
The section on why you should host your Linux guests on IBM z Systems highlights many of the technical reasons why installations should deploy KVM for IBM z Systems, focused on RAS and virtualization strengths of the platform. Starting with hardware-enabled virtualization, many of the virtualization and availability features provide a strong platform for hosting your business applications on Linux servers.
Following a summary of High Availability recommendations, we provide a high-level description of the KVM on z Systems HA environment and describe a starting point for you to build your KVM on z Systems environment, with a goal of avoiding single points of failure in the hypervisor environment and providing a high availability environment for your Linux guest virtual machines.
Access the white paper at: https://ibm.biz/BdHhGt
Bob Abrams
Scott Loveland
Viktor Mihajlovski
Reinhard Buendgen
Steven Cook