2. Red Hat Enterprise Virtualization Resources

The Red Hat Enterprise Virtualization platform manages the following resources within the management infrastructure to create a powerful, scalable virtual environment. The components of the Red Hat Enterprise Virtualization platform fall into three categories: physical components, logical components, and resources. Physical components are the objects that occupy physical space in the world and make up a part of the Red Hat Enterprise Virtualization platform, and may be thought of as the "hardware" component of the platform. Logical components are the non-physical groupings and processes that enable Red Hat Enterprise Virtualization to provide its functionality, and may be thought of as the "software" component of the platform. Resources are administration tools and devices made available to the administrator by the Red Hat Enterprise Virtualization platform, and may be thought of as the "utilities" provided by the "software" of the logical components, which runs on the "hardware" of the physical components.
  • Hosts - A host is a physical server (a physical machine) that runs either Red Hat Enterprise Virtualization Hypervisor or Red Hat Enterprise Linux 5.5 and above, and hosts one or more virtual machines. Hosts are grouped into clusters. Virtual machines can be migrated from one host to another within a cluster.
  • Clusters - A cluster is a set of physical hosts that are treated as a resource pool for a set of virtual machines. Hosts in a cluster share the same network infrastructure and the same storage. They form a migration domain within which virtual machines can be moved from host to host.
  • Data Center - A data center is a logical entity that defines the set of resources used in a specific environment. It is a collection of a number of clusters of virtual machines, storage and networks.
    The data center is the highest level container for all physical and logical resources within a managed virtual environment.
    A data center relies on adequate and accessible physical storage. The storage pool provides an abstracted view of the physical storage assigned to a data center, that enables planners and administrators to easily monitor and manage storage requirements.
  • Storage Pool - The storage pool is a logical entity that contains a standalone image repository of a certain type, either iSCSI, or Fiber Channel, or NFS. Each storage pool can contain several storage domains, for virtual machine disk images and for ISO images and for the import and export of virtual machine images.
  • Virtual Machines - A virtual machine is a virtual desktop or virtual server containing an operating system and a set of applications. Multiple identical desktops can be created in a Pool. Virtual machines can be accessed and used by end users, and created, managed or deleted by power users.
  • Desktop Pools - A desktop pool is a group of identical virtual desktops that are available on demand by each one of the group members (not concurrently). Desktop pools can be set up for different purposes. For example, one desktop pool may be for the Marketing department, another for Research and Development, and so on. Users get available desktops of the required type from the appropriate pool.
  • Templates - A template is a model virtual machine with a unique configuration and settings. A virtual machine that is based on a particular template acquires the configurations and settings of the template. Templates are used to conveniently and efficiently create a set of identical virtual machines. Using templates is the quickest way of creating large number of virtual machines in a single step.
  • Snapshots - A snapshot is a view of a virtual machine's operating system and all its applications at a given point in time. It can be used to save the settings of a virtual machine before an upgrade, or before new applications are installed. In case of problems, the parameters from the snapshot can be used to restore the virtual machine to the state before the upgrade or installation.
  • User Types - Red Hat Enterprise Virtualization supports multiple levels of administrators and users with distinct levels of permissions. System administrators can manage and administrate objects of the physical infrastructure, such as data centers, hosts and storage. Red Hat Enterprise Virtualization Power Users are administrators who manage the end-users of the virtual machines, as well as act as administrators of the virtual machines. End users are the users who have access to a specified desktop, or an available virtual machine from a designated desktop pool.
  • Events and Monitors - Alerts, warnings, and other notices about activities within the system help the administrator to monitor the performance and running of various resources. Monitoring details can be displayed in both graphic and textual fashion.
  • Reports - A range of reports either from the reports module based on JasperReports, or from the data warehouse. Preconfigured or ad hoc reports can be generated from the reports module. Users can also generate reports using any query tool that supports SQL from a data warehouse that collects monitoring data for hosts, virtual machines and storage.