Home > Storage > Unity XT > Storage Admin > Dell Unity: Data Reduction > Enabling and Disabling Data Reduction on an Existing Storage Resource
Dell Unity Data Reduction, along with Advanced Deduplication, can be enabled or disabled on supported storage resources at any point in time. This can easily be accomplished using either Unisphere, Unisphere CLI, or REST API. The following sections outline how you can easily enable and disable the options on existing storage resources using Unisphere and Unisphere CLI.
To enable and disable data reduction and Advanced Deduplication on an existing LUN, review the properties of the LUN from the Block page. The Block page can be accessed by selecting Block under Storage in the left Unisphere pane. After double clicking the Name of the LUN, or after selecting a LUN and clicking the Pencil (View/Edit) icon, the LUN Properties window is displayed. On the General tab, a checkbox for Data Reduction exists. Depending if data reduction is currently disabled or enabled on the storage resource, the box will either be unchecked or checked. To change the state of data reduction, simply check or uncheck the Data Reduction box and click Apply. Advanced Deduplication is only available once Data Reduction is enabled and the configuration supports it. Advanced Deduplication can be enabled or disabled independently to the Data Reduction setting. To change the state of Advanced Deduplication, simply check or uncheck the Advanced Deduplication box and click Apply.
Error! Reference source not found. below shows the Properties window of a LUN which currently has Data Reduction disabled. The Data Reduction box has been selected to enable data reduction on the resource but Apply has not yet been selected. When enabling data reduction on a resource, an informational message is displayed after checking the Data Reduction box. A similar message appears when Data Reduction is enabled, and the Advanced Deduplication box has been checked but Apply has not been selected. The message when enabling Data Reduction states:
Only the newly written data will have data reduction applied. Existing data will remain unchanged.
Figure 14. LUN Properties Window. Enabling Data Reduction Example
Error! Reference source not found. below shows the Properties window of a LUN which currently has Data Reduction and Advanced Deduplication enabled. The Advanced Deduplication box has been deselected to disable Advanced Deduplication on the resource but Apply has not yet been selected. When disabling Advanced Deduplication on a resource, an informational message is displayed after unchecking the Advanced Deduplication box. A similar message appears when Data Reduction is disabled but Apply has not been selected. The message when disabling Advanced Deduplication states:
Newly written data will not have advanced deduplication applied. Existing data will remain unchanged.
This message implies that the Local LUN Move option must be used to remove all Advanced Deduplication savings from the existing data within the storage resource if desired. If the Local LUN Move option is not utilized, then only overwrites to the LUN will cause Advanced Deduplication savings to decrease.
Figure 15. LUN Properties Window. Disabling Advanced Deduplication Example
Enabling and disabling data reduction, along with Advanced Deduplication, on a LUN within a Consistency Group can be accomplished by first navigating to the Consistency Group tab within the Block page. From this page either double click the Name of a Consistency Group, or after selecting a Consistency Group click the Pencil (View/Edit) icon. This will open the Consistency Group Properties window. An example of this window can be seen in Figure 16.
Figure 16. Consistency Group Properties Window
After opening the Consistency Group Properties window, navigate to the LUNs tab. From this screen you can view the current LUNs within the Consistency Group, and the current state of data reduction and Advanced Deduplication if the Data Reduction and Advanced Deduplication columns are displayed. A sample of the LUNs tab is shown in Error! Reference source not found.. To edit the settings of one of the LUNs, double click the LUN or select the LUN and click the Pencil icon.
Figure 17. Consistency Group – LUNs Tab
The LUN Properties window is now shown. This is the exact same Properties window as a LUN not currently in a Consistency Group. An example of this window is shown in Error! Reference source not found.. As mentioned previously, to enable or disable data reduction, along with Advanced Deduplication on a LUN, simply check or uncheck the Data Reduction or Advanced Deduplication box and click Apply. The new state for data reduction and Advanced Deduplication are reflected in the LUNs tab within the Consistency Group Properties window.
Figure 18. LUN Properties Window
Data reduction can be enabled or disabled at any time on File Systems created on Dell UnityOS version 4.2 or later if they reside within a supported configuration. Advanced Deduplication can also be enabled or disabled at any point in time. To modify these settings, first navigate to the File page by selecting File under Storage in the left Unisphere pane. In this window, all existing File Systems on the system are displayed. To modify the data reduction or Advanced Deduplication setting on a File System, double click on a supported File System to modify it or select a File System and select the Pencil icon. The Properties window is now shown. To enable or disable data reduction, simply check or uncheck the Data Reduction box and click Apply. Likewise, to enable or disable the Advanced Deduplication setting on supported configurations, check or uncheck the Advanced Deduplication box and hit apply. A sample of the Properties window for a data reduction enabled File System is shown in Error! Reference source not found.. The File System currently has Data Reduction disabled, and the Data Reduction box has been selected to enable data reduction on the resource but Apply has not yet been selected. When enabling data reduction on a resource, an informational message is displayed after checking the Data Reduction box. A similar message is displayed when enabling Advanced Deduplication. The message when enabling Data Reduction on a File System states:
Only the newly written data will have data reduction applied. Existing data will remain unchanged.
This message outlines that only new writes to the File System or overwrites to existing data within the File System are considered for data reduction.
Figure 19. File System Properties Window – Enabling Data Reduction
When reviewing the Properties window for a File System which does not support data reduction, no option to enable data reduction will be shown. This is true for Thick File Systems, and any File Systems created on a code previous to Dell UnityOS version 4.2. Error! Reference source not found. below shows an example of the File System Properties window for a Thick File System. As you can see no option for data reduction is shown.
Figure 20. File System Properties Window – Data Reduction Not Supported
File System Properties Window – Disabling Advanced Deduplication below shows the Properties window of a File System which currently has data reduction enabled. The Advanced Deduplication box has been deselected to disable Advanced Deduplication on the resource but Apply has not yet been selected. When disabling Advanced Deduplication on a resource, an informational message is displayed after unchecking the Advanced Deduplication box. The message states:
Newly written data will not have advanced deduplication applied. Existing data will remain unchanged.
This message implies that only overwrites to the File System will cause data reduction savings to decrease.
Figure 21. File System Properties Window – Disabling Advanced Deduplication
Enabling or disabling data reduction and Advanced Deduplication on existing VMware VMFS or NFS Datastores can be accomplished at any time through Unisphere, Unisphere CLI, or REST API. To enable or disable these features in Unisphere, first navigate to the VMware page within Unisphere. To do so, select VMware under Storage in the left Unisphere pane. All existing VMware Datastores are displayed on this page. To modify the VMware Datastore, double click on a Datastore, or select the Datastore and select the Pencil icon. The Properties window is now shown. To enabled or disable data reduction, simply check or uncheck the Data Reduction box and click Apply. To enabled or disable Advanced Deduplication, check or uncheck the Advanced Deduplication box and hit Apply. A sample of the Properties window for a VMware VMFS Datastore is shown in Error! Reference source not found..
Figure 22. VMware VMFS Datastore – Properties Window
For VMware NFS Datastores, data reduction is only supported if the resource is Thin, resides on a supported Pool configuration, and is created while the system is running Dell UnityOS version 4.2 or later. If the resource supports data reduction, data reduction can be enabled or disabled at any time. If the resource is Thick, or was created on an earlier code, Unisphere will not display an option to enable data reduction. When attempting to enable or disable data reduction on a resource which does not support data reduction via Unisphere CLI or REST API, an error will be returned. Advanced Deduplication is only supported on resources which support Data Reduction, and currently reside on a configuration which supports Advanced Deduplication.