Using Snapshot And Disk Copy Together; Multi-Path Software - Dell PowerVault MD3220 Owner's Manual

Ensure that you record the LUN used to provide access to the source virtual
disk. You need this information when you define a host server-to-virtual disk
mapping for the target (backup) virtual disk. Also, be sure to stop all I/O
activity to the source virtual disk before beginning the virtual disk recovery
procedure.

Using Snapshot and Disk Copy Together

You can use the Snapshot Virtual Disk and Virtual Disk Copy premium
features together to back up data on the same storage array, or to restore the
data on the snapshot virtual disk to its original source virtual disk.
You can copy data from a virtual disk in one of two ways:
• By taking a point-in-time snapshot of the data
• By copying the data to another virtual disk using a virtual disk copy
You can select a snapshot virtual disk as the source virtual disk for a virtual
disk copy. This configuration is one of the best ways you can apply the
snapshot virtual disk feature, since it enables complete backups without any
impact to the storage array I/O.
You cannot use a snapshot repository virtual disk as a source virtual disk or as
a target virtual disk in a virtual disk copy. If you select the source virtual disk
as the target virtual disk of a virtual disk copy, you must disable all snapshot
virtual disks associated with the source virtual disk.

Multi-Path Software

Multi-path software (also referred to as the failover driver) is software resident
on the host server that provides management of the redundant data path
between the host server and the storage array.
The multi-path software identifies the existence of multiple paths to a virtual
disk and establishes a preferred path to that disk. If any component in the
preferred path fails, the multi-path software automatically re-routes I/O
requests to the alternate path so that the storage array continues to operate
without interruption.
NOTE:
Multi-path software available on the MD3200 series resource media.
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Planning: MD3200 Series Storage Array Terms and Concepts