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Storage partitioning, Defining additional mappings. see – Dell POWERVAULT MD3600I User Manual

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allows only LUNs up to 31, you cannot move that restricted host type into a storage partition that has LUNs

greater than 31 already mapped.

The Default Group on the Host Mappings tab has a default host type. To change the host type, right-click on the host and
select Change Default Host Operating System from the pop-up menu. If you set the default host type to a host type that is
restricted, the maximum number of LUNs allowed in the Default Group for any host is restricted to the limit imposed by
the restricted host type. If a particular host with a non-restricted host type becomes part of a specific storage partition,
you are able to change the mapping to a higher LUN.

Storage Partitioning

A storage partition is a logical entity consisting of one or more virtual disks that can be accessed by a single host or
shared among hosts that are part of a host group. The first time you map a virtual disk to a specific host or host group, a
storage partition is created. Subsequent virtual disk mappings to that host or host group do not create another storage
partition.
One storage partition is sufficient if:

Only one attached host accesses all of the virtual disks in the storage array

All attached hosts share access to all of the virtual disks in the storage array

When you choose this type of configuration, all of the hosts must have the same operating system and special software
(such as clustering software) to manage virtual disk sharing and accessibility.
More than one storage partition is required if:

Specific hosts must access specific virtual disks in the storage array

Hosts with different operating systems are attached to the same storage array. In this case, a storage partition

is created for each host type

You can use the Storage Partitioning Wizard to define a single storage partition. The Storage Partitioning Wizard guides
you through the major steps required to specify which host groups, hosts, virtual disks, and associated logical unit
numbers (LUNs) are to be included in the storage partition.
Storage partitioning fails when:

All mappings are defined

You create a mapping for a host group that conflicts with an established mapping for a host in the host group

You create a mapping for a host in a host group that conflicts with an established mapping for the host group

Storage partitioning is unavailable when:

No valid host groups or hosts exist in the object tree on the Host Mappings tab

No host ports are defined for the host being included in the storage partition

All mappings are defined

NOTE: You can include a secondary virtual disk in a storage partition. However, any hosts that are mapped

to the secondary virtual disk has read-only access until the virtual disk is promoted to a primary virtual

disk, or the mirror relationship is removed.

Storage partitioning topology is the collection of elements, such as Default Group, host groups, hosts, and host ports
shown as nodes in the object tree of the Host Mappings tab in the AMW. For more information, see

Using The Host

Mappings Tab

.

If a storage partitioning topology is not defined, an informational dialog is displayed each time you select the Host
Mappings tab. You must define the storage partitioning topology before you define the actual storage partition.

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