Glossary

Supported on Integrity Virtual Machines running HP-UX 11i v3, a storage device addressing model that addresses a logical unit (referred to as LUN, this is the logical device that refers to the physical storage device) by using the same device special file (DSF) regardless of the location of the LUN. The addressing model uses a worldwide device identifier (WWID) to uniquely identify LUNs. The WWID is a device attribute that is independent of the device’s location in a SAN or in an adapter/controller access path. With a multipath device, the WWID allows one persistent DSF and one LUN hardware path to represent the device, regardless of the number of legacy hardware paths. Therefore, an agile device address remains the same (is persistent) when changes are made to the access path. Likewise, if additional paths are offered to a given LUN (by adding a new SCSI controller or new SCSI target paths), the DSF is unaffected: no new DSFs need be provided. This model enables VM Manager to display one DSF for each multipath device instead of displaying a separate DSF for each path to the device (as done when using the legacy addressing scheme).

Automatic Port Aggregation. A combination of LAN ports that can be accessed through a single interface name. An APA creates link aggregates (often called trunks) that provide a logical grouping of two or more physical ports into a single “fat pipe.” This port arrangement provides more data bandwidth and higher reliability than would otherwise be available.

Accelerated Virtual Input/Output. An I/O protocol that improves virtual I/O performance for network and storage devices used within the Integrity Virtual Machines environment. The protocol also enables support for a greater number of virtual I/O devices per guest. For each virtual machine containing an AVIO device, the VM Host OS and the guest OS must support AVIO.

Backing store. The physical device (such as a network adapter, a disk, or a file) on the VM Host that is allocated to guests.

Two or more systems configured together to host workloads. Users are unaware that more than one system is hosting the workload.

The actual data-processing engine within a processor. A single processor might have multiple cores, and a core might support multiple execution threads. A virtual processor core in a virtual machine is also called a virtual CPU or vCPU.

A vswitch that is dedicated to use by a certain virtual machine. This type of vswitch cannot be shared by multiple virtual machines running at the same time.

Extensible Firmware Interface. The system firmware user interface that allows boot-related configuration changes and operations on Itanium-based systems. For example, EFI provides ways to specify boot options and list boot devices.

The amount of a system resource (for example, processor resources) that is guaranteed to a virtual machine. The actual allocation of resources to the virtual machine can be greater or less than its entitlement, depending on the virtual machine's demand for processor resources and the overall system processor load.

The maximum amount of computing power allotted to a virtual machine for each vCPU.

The virtual machine running the guest OS and guest applications.

Guest operating system.

HP Integrity Virtual Machines (Integrity VM). The HP product that allows you to install and run multiple systems (virtual machines) on the same physical host system.

The storage device addressing model that uses the device special file (DSF) path as defined in HP-UX 11i v2 and earlier versions. In contrast to the agile addressing model introduced with HP-UX 11i v3, the legacy device special file (DSF) is bound to a specific hardware path to a storage device. For this reason, a device with multiple paths is represented by several legacy DSFs. If the physical storage device is reconnected to a host through a different host bus adapter (HBA) or a different target port, the address represented by the DSF is affected, requiring reconfiguration of applications, volume managers, or file systems. Likewise, if additional paths are offered to a given LUN (through the addition of a new SCSI controller or new SCSI target paths), an equal number of additional DSFs are required to address them.

A vswitch created by default when Integrity Virtual Machines is installed on a VM Host. The local network created by this vswitch can be used for communications among guests but not for communication between the VM Host and any guest or between any external system and a VM guest.

A system running under HP SIM. Systems become managed nodes through the HP SIM discovery mechanism.

Network interface card. Also called LAN card, LAN adapter, or PPA.

Also referred to as the central processor unit (CPU), a processor is the hardware component in a computer that processes instructions and plugs into a processor socket. A processor can contain more than one core.

HP Serviceguard. A product that allows you to create high-availability clusters of HP 9000 or HP Integrity servers. Serviceguard can be used to manage virtual machines as Serviceguard packages. A Serviceguard package groups application services (individual HP-UX processes) together and maintains them on multiple nodes in the cluster, making them available for failover.

A vswitch that can be used by more than one active virtual machine.

Virtual CPU. A single-core virtual processor in a virtual machine.

A software entity provided by Integrity Virtual Machines. Integrity Virtual Machines allows a single server or nPartition to act as a VM Host for multiple individual virtual machines, each running its own instance of an operating system (called a guest OS). Virtual machines (also called VMs) are servers in the Virtual Server Environment (VSE).

The user-mode application that provides console emulation for virtual machines. Each instance of the virtual machine console is one console session for its associated virtual machine.

A LAN that is shared by the virtual machines running on the same VM Host or in the same Serviceguard cluster.

Virtual LAN. Defines logical connectivity instead of the physical connectivity defined by a LAN. A VLAN provides a way to partition a LAN logically such that the broadcast domain for a VLAN is limited to the nodes and switches that are members of the VLAN.

The virtual machine host system.

Virtual switch. Refers to both a dynamically loadable kernel module (DLKM) and a user-mode component implementing a virtual network switch. The virtualized network interface cards (NICs) for guest machines are attached to the virtual switches. By associating the vswitch with a physical working LAN on the VM Host, you provide the guest with the capability of communicating outside the localnet.

Web-Based Enterprise Management. A set of web-based information services standards developed by the Distributed Management Task Force, Inc. A WBEM Provider offers access to a resource. WBEM clients send requests to providers to get information about, and access to, the registered resources.