Dell POWERVAULT MD3600I - Manual (Page 137)

– Select An existing snapshot image and then select a snapshot image from the snapshot image table and
click Next.
– Select A new snapshot image (on an existing snapshot group) and then a snapshot group from the existing
snapshot group table and then click Next.
The Snapshot Virtual Disk Settings window is displayed.
4. In the Snapshot virtual disk name field, enter a unique name (30 character maximum) that best describes the virtual
disk selected for this snapshot image, for example, AccountingData.
By default, the snapshot virtual disk name is shown in the name text box as follows:
[base-virtual disk-name] - SV + sequence-number
In this example, SV (snapshot virtual disk) is the appended suffix and sequence-number is the chronological
number of the snapshot virtual disk relative to the base virtual disk.
For example, if you create the first snapshot virtual disk for a base virtual disk called “Accounting”, the default
name of the snapshot virtual disk is “Accounting_SV_01”. The default name of the next snapshot virtual disk you
create based on “Accounting” is “Accounting_SV_02”.
There is a 30-character limit. After you reach this limit, you can no longer type in the text box. If the base virtual disk
is 30 characters, the default name for the group uses the base virtual disk name truncated enough to add the suffix
“SV” and the sequence string.
5. In the Map to host drop-down, specify how you want to map the host to the snapshot virtual disk.
– Map Now to Default Group – The virtual disk is automatically assigned a logical unit number (LUN) and is
accessible by any hosts that are connected to the storage array.
– Map Later – The virtual disk is not assigned a LUN and is not accessible by any hosts until you go to the
Host Mappings tab and assign a specific host and LUN to this virtual disk.
– Select a specific host – You can select a specific host or host group from the list. This option is available
only if Storage Partitioning is enabled.
NOTE: Make sure there are enough free LUNs on the host or host group that you selected to map to a
snapshot virtual disk.
6. Select how to grant host access to the snapshot virtual disk. Do one of the following:
– Select Read Write and go to step 7.
– Select Read Only and click Finish to create the snapshot virtual disk. Go to step 8.
NOTE: Repositories are not required for Read Only snapshot virtual disks.
Keep these guidelines in mind when you grant host access to a snapshot virtual disk:
– Each host has its own logical unit number (LUN) address space and allows the same LUN to be used by
different host groups or hosts to access snapshot virtual disks in a storage array.
– You can define one mapping for each snapshot virtual disk in the storage array.
– Mappings are shared between controllers in the storage array.
– The same LUN cannot be used twice by a host group or a host to access a snapshot virtual disk. You must
use a unique LUN.
– An access virtual disk mapping is not required for out-of-band storage arrays.
7. Choose how you want to create the repository for the Read-Write snapshot virtual disk. Do one of the following:
– Select Automatic and click Finish to create the snapshot virtual disk repository with the default capacity
settings. This option is the recommended one.
– Select Manual and click Next to define the properties for the snapshot virtual disk repository. Then click
Finish to continue with the snapshot virtual disk creation procedure.
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