Using HP Serviceguard for Linux with Red Hat KVM Guests, May 2013

Technical white paper | Using HP Serviceguard for Linux with Red Hat KVM Guests

Introduction

Virtual machines are increasingly being deployed for server consolidation and flexibility. Virtual machine technology allows

one physical server to simulate multiple servers, each concurrently running its own OS. In virtual machine technology, the

virtualization layer also known as hypervisor

abstracts the physical resources so that each instance of an OS appears to

have its own NIC, processor, memory etc when in fact they are virtual instances. This allows you to replace a number of

existing physical servers with virtual machines.

The Linux KVM is an offering from Red Hat Enterprise Linux (RHEL) for a complete virtualization solution. This document

explains how you can use HP Serviceguard for Linux in RHEL KVM-based virtualization environments to provide

mission-critical clustering and failover capabilities. It also makes recommendations for eliminating single point of failure

(SPOF) that you can implement.

KVM terminology used in this document

Table 1. KVM terminology used in this document

Term Definition

KVM Kernel-based virtual machine

KVM Host, Host Physical server on which KVM Hypervisor is installed

KVM Guest, Guest, VM KVM virtual machine carved out of the hypervisor

Physical Machine Physical server configured as a Serviceguard cluster node

Bridge A device bound to a physical network interface on the host which enables

any number of guests to connect to the local network on the host. It is

mapped to a physical NIC which acts as a switch to KVM Guests

Cluster, Serviceguard Cluster HP Serviceguard for Linux cluster

Introduction to KVM

HP Serviceguard for Linux solutions can be used in KVM based virtualization environments to provide mission-critical

clustering and failover capabilities. Linux KVM is provided by RHEL as a full virtualization solution. KVM differs from other

popular alternatives like Xen and VMware in terms of operation, performance and flexibility. KVM comes as a kernel module,

with a set of user space utilities to create and manage the virtual machines.

Kernel-based Virtual Machine technology includes the following:

• A full virtualization solution for Linux on AMD64 and Intel® 64 hardware.

• Each KVM virtualized guest or “VM guest” is run as a single Linux process.

• A hypervisor-independent virtualization API, “libvirt,” which provides common generic and stable layer to securely

manage VM guests on a host.

• A command line tool “virsh” used to manage the VM guests.

• A graphical user interface (GUI) “virt-manager” for managing the VM guests.

Hypervisor often refers to a layer that resides directly on server hardware, but terms are not used consistently across the industry.