RHEV has two separate distinct layers, the hypervisor itself and management. The hypervisor layer, RHEV-H is of course built on Red Hat Enterprise Linux (RHEL) and utilizes KVM for the hypervisor technology. RHEV-H can be configured using pre-built RHEV-H image or using standard RHEL. The management layer, Red Hat Enterprise Virtualization Management (RHEV-M) provides management for a multi-hypervisor environment and uses concepts such as datacenters, clusters, networks and storage domains to describe virtualization resources. In this article we will focus on options for configuring RHEV-M. The upstream opensource project behind RHEV-M is oVirt. There are two options as of RHEV 3.5 for configuring RHEV-M, standalone or hosted engine.
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