vSphere Storage - ESXi 5.1 - Documentation - VMware

vSphere Storage
Figure 1-5. Target and LUN Representations
target
LUN LUN LUN
storage array
target target target
LUN LUN LUN
storage array
In this illustration, three LUNs are available in each configuration. In one case, the host sees one target, but
that target has three LUNs that can be used. Each LUN represents an individual storage volume. In the other
example, the host sees three different targets, each having one LUN.
Targets that are accessed through the network have unique names that are provided by the storage systems.
The iSCSI targets use iSCSI names, while Fibre Channel targets use World Wide Names (WWNs).
NOTE ESXi does not support accessing the same LUN through different transport protocols, such as iSCSI and
Fibre Channel.
A device, or LUN, is identified by its UUID name. If a LUN is shared by multiple hosts, it must be presented
to all hosts with the same UUID.
Storage Device Characteristics
You can display all storage devices or LUNs available to the host, including all local and networked devices.
If you use third-party multipathing plug-ins, the storage devices available through the plug-ins also appear
on the list.
For each storage adapter, you can display a separate list of storage devices available for this adapter.
Generally, when you review storage devices, you see the following information.
Table 1-1. Storage Device Information
Storage Device Information Description
Name Also called Display Name. It is a name that the ESXi host assigns to the device based on
the storage type and manufacturer. You can change this name to a name of your choice.
Identifier A universally unique identifier that is intrinsic to the device.
Runtime Name (vSphere Client
only)
The name of the first path to the device.
Operational State Indicates whether the device is mounted or unmounted. For details, see “Detach Storage
Devices,” on page 139.
LUN Logical Unit Number (LUN) within the SCSI target. The LUN number is provided by the
storage system. If a target has only one LUN, the LUN number is always zero (0).
Type Type of device, for example, disk or CD-ROM.
Drive Type Information about whether the device is a solid-state drive (SSD) or a regular non-SSD
hard drive. For details, see Chapter 16, “Solid State Disks Enablement,” on page 145.
Transport Transportation protocol your host uses to access the device.
Capacity Total capacity of the storage device.
Owner The plug-in, such as the NMP or a third-party plug-in, that the host uses to manage paths
to the storage device. For details, see “Managing Multiple Paths,” on page 198.
Hardware Acceleration Information about whether the storage device assists the host with virtual machine
management operations. The status can be Supported, Not Supported, or Unknown. For
details, see Chapter 21, “Storage Hardware Acceleration,” on page 215.
Location A path to the storage device in the /vmfs/devices/ directory.
18 VMware, Inc.