HP SAN Virtualization Services Platform User Manual
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mirroring
The creation and continuous updating of one or more redundant copies of data,
usually for the sake of fault or disaster recovery.
OpenVMS Unit ID
Abbreviated as OUID. A storage element identifier that is necessary for hosts
running OpenVMS to interact with the storage elements presented to them. This
identifier is relevant to virtual disks, snapshots, and synchronous mirror groups.
passive path
A path that must have some operation (for example, a SCSI start unit command
that is issued by the server) performed on it to make it active.
See also
active/active RAID
,
active/passive RAID
, and
secondary path
.
patch file
Incremental update to an existing system image.
persistent
reservation
A mechanism for the resolution of dynamic SCSI contention in systems with
multiple initiator ports accessing a logical unit, whereby a single initiator port
or a set of initiator ports can reserve the logical unit indefinitely. While reserved,
the storage device server rejects all commands for that logical unit from any other
initiator ports.
personality
The way in which a DPM exposes LUNs to the hosts that use them. Exposing a
LUN with the correct personality (such as HP EVA VS-ALUA or HP EVA MS-DPM)
for the hosts enables features such as failover and failback between DPMs in
conjunction with the appropriate multipath software running on the host. See the
HP StorageWorks SAN Virtualization Services Platform Manager User Guide
for a list of personalities used with SVSP.
physical disk
A disk device that can be discovered and managed by VSM.
PiT
Point-in-Time. A VSM term denoting an entity created by a snapshot that represents
the freezing of a virtual disk’s data at a particular time and the redirection of
any further modifications to the virtual disk’s data to a new virtual disk, called a
temporary virtual disk.
POST
Power-on Self Test. The diagnostic sequence executed by devices during system
startup.
primary path
For an active/active or active/passive device, a path belonging to the set of
paths that are active by default, as viewed by the server.
See also
active/passive RAID
,
active path
, and
secondary path
.
PSC
Physical storage container. A path from a DPM to a back-end LU. There are eight
PSCs between any two DPM initiator ports and a back-end LU presented to the
domain by an eight-port storage array (for example, an HP EVA8100).
SAN
Storage Area Network. A network specifically dedicated to the task of transporting
data between storage systems and servers. SANs are traditionally connected
over FC networks but have also been built using iSCSI technology.
secondary path
For an active/passive device, the set of paths that are passive by default.
See also
active/passive RAID
,
passive path
, and
primary path
.
setup virtual disk
A virtual disk that contains the virtualized VSM configuration for the SVSP domain,
including, for example, information about storage pools and virtual disks defined
on the domain.
Glossary
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