Users Guide

See the Dell EqualLogic Group Manager Administrator’s Guide for more information about thin clones.
ASM/ME supports the following operations on thin clone volumes:
● Taking a snapshot
● Replicating a thin clone volume
● Cloning a thin clone volume, which creates a new thin clone volume under the template volume
ASM/ME supports the following operations on template volumes:
● Creating a thin clone from the template volume
● Cloning the template volume, which results in a new template volume
NOTE: Snapshots and replication of template volumes are not supported.
Robust Data Recovery
ASM/ME enables you to implement different data recovery strategies by recovering data directly from a Smart Copy. The
principal methods of recovering data from Smart Copies are:
● In-Place Recovery—A full recovery method that restores all data in a volume. You can use this recovery option for snapshot
Smart Copies of generic data volumes or for application components. Application components might consist of Exchange
mailbox databases, SQL Server databases, or Hyper-V virtual machines.
● Selective Component Recovery—A selective restore of files or components. Selective restore is supported only for
components belonging to certain applications. Some constraints apply to recovery methods and supported Smart Copy
types. These constraints are identified in the section for each supported application.
● Manual Recovery—You can use ASM/ME to mount a snapshot Smart Copy and manually copy over data from the mounted
Smart Copy.
Thin-Provisioning a Volume
On a PS Series group, the storage for a thin-provisioned volume is allocated incrementally as the volume uses more space. The
full amount of space reserved for the volume is not immediately allocated when the volume is created. Over time, however, as
data is written to thin-provisioned volumes, they lose their space efficiency because the group has no way to release storage
that is no longer in use by the volume (for example, because files were deleted).
HIT/Microsoft includes tools for managing thin-provisioned volumes on PS Series groups running firmware version 9.0 or later.
These tools are available on all supported Microsoft operating systems.
● You can thin-provision a volume through the ASM/ME GUI, both as a one-time operation and through schedules. See About
Thin-Provisioning Volumes in HIT/Microsoft and Schedules for Thin-Provisioning for more information.
● The Host Integration Tools include a command-line utility called eqlrethin.exe (see the Host Integration Tools for
Microsoft Installation and User’s Guide).
● The Dell EqualLogic PowerShell Tools include a cmdlet called Invoke-RethinEqlVolume. See the Dell EqualLogic
PowerShell Tools Reference Guide for detailed information about this cmdlet.
Windows Server 2012 R2 or later automatically performs thin-provisioning. Typically, Windows thin-provisions the volume soon
after a file is deleted.
For replicated volumes (including SyncRep), Dell recommends that you disable the SCSI unmap support in Windows Server 2012
R2 or later. See the Dell EqualLogic Group Manager Administrator’s Guide for more information, which describes the effects of
SCSI unmap operations.
NOTE:
When you disable unmap support, the Host Integration Tools thin-provisioning feature does not work. To thin-
provision a volume, you must use the Windows Disk Optimization tool.
SAN Data Copy Offload
ASM/ME uses SAN Data Copy Offload to perform its selective restore operations. SAN Data Copy Offload is a Dell EqualLogic
API that accelerates file copy operations by using SCSI Extended Copy commands.
SAN Data Copy Offload frees up server resources and decreases the time it takes to perform selective restores. For example,
assume multiple volumes are residing on a PS Series group. If those volumes are mounted on a Windows server, copying a file or
Introduction to ASM/ME
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