Dell POWERVAULT MD3600I - Manual (Page 28)

part of a host group that shares access to one or more virtual disks. You can manually configure a host server-to-virtual
disk mapping. When you configure host server-to-virtual disk mapping, consider these guidelines:
• You can define one host server-to-virtual disk mapping for each virtual disk in the storage array.
• Host server-to-virtual disk mappings are shared between RAID controller modules in the storage array.
• A unique LUN must be used by a host group or host server to access a virtual disk.
• Not every operating system has the same number of LUNs available for use.
Host Types
A host server is a server that accesses a storage array. Host servers are mapped to the virtual disks and use one or
more iSCSI initiator ports. Host servers have the following attributes:
• Host name — A name that uniquely identifies the host server.
• Host group (used in Cluster solutions only) — Two or more host servers associated together to share access to
the same virtual disks.
NOTE: This host group is a logical entity you can create in the MD Storage Manager. All host servers in a
host group must be running the same operating system.
• Host type — The operating system running on the host server.
Advanced Features
The RAID enclosure supports several advanced features:
• Virtual Disk Snapshots.
• Virtual Disk Copy.
• Remote replication (standard and legacy-based). For more information, see Premium Feature - Remote
Replication and Premium Feature- Remote Replication (Legacy) .
NOTE: The premium features listed above must be activated separately. If you have purchased these features, an
activation card is supplied that contains instructions for enabling this functionality.
Types Of Snapshot Functionality Supported
The following types of virtual disk snapshot premium features are supported on the MD storage array:
• Snapshot Virtual Disks using multiple point-in-time (PiT) groups — This feature also supports snapshot groups,
snapshot images, and consistency groups.
• Snapshot Virtual Disks (Legacy) using a separate repository for each snapshot
For more information, see Premium Feature---Snapshot Virtual Disk and Premium Feature—Snapshot Virtual Disks
(Legacy) .
Snapshot Virtual Disks, Snapshot Images, And Snapshot Groups
A snapshot image is a logical image of the content of an associated base virtual disk created at a specific point-in-time.
This type of image is not directly readable or writable to a host since the snapshot image is used to save data from the
base virtual disk only. To allow the host to access a copy of the data in a snapshot image, you must create a snapshot
virtual disk. This snapshot virtual disk contains its own repository, which is used to save subsequent modifications made
by the host application to the base virtual disk without affecting the referenced snapshot image.
Snapshot images can be created manually or automatically by establishing a schedule that defines the date and time
you want to create the snapshot image. The following objects can be included in a snapshot image:
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