Change Logical Unit Capacity

This help page provides information to guide you through the procedure to change the LU capacity and contains the following topics:

 

NOTE: This feature is separate from the previous LUN expansion feature used in legacy arrays call Logical Unit Size Expansion (LUSE). Click here for more information on the LUSE feature.

Overview  

From the Change Logical Unit Capacity window, you can expand (grow) or reduce (shrink) the logical unit and create or separate logical unit expansion. The Change Logical Unit Capacity window may be accessed from the following two windows.

Requirements and Conditions   (back to top)

This section provides important requirements and conditions required to increase LU capacity properly.

General Conditions

  1. You cannot delete an LU whose status of the forced parity correction is any of the following status messages observed in the RAID group of the expansion target:

  2. ”Correcting”

  3. ”Waiting”

  4. ”Waiting Drive Reconstruction”

  5. ”Unexecuted”, ”Unexecuted 1” or ”Unexecuted 2”   

If any of the above messages are displayed, you need to execute a forced parity correction for this LU and change the LU status to ”Correction Completed” or "Skip," and then delete this LU.

  1. You cannot execute an LU expansion they are being formatted..

  2. You cannot execute an LU expansion for a unified LU configured using LUs of two or more RAID groups.

  3. You cannot execute an LU expansion during a drive restoration is in progress on the affected LU. Execute after completing the drive restoration.

  4. You cannot expand the following LU types:

  1. You cannot expand LUs of the RAID group in which the Power Saving function is set. Change the status of the Power Saving feature to "Normal (spin-up)” and then expand the LUs.

Additional Notes on the LU Expansion Process   (back to top)

  1. You cannot reduce an LU where its properties are set to "Read Only," "Protect," or "Can't Guard."

  2. You cannot reduce an LU where the S-VOL setting is ”Setting Impossible (disabled)” and the mode is any of the following:

  3.  ”Read Capacity 0 (Zer)”

  4. ”Inquiry Command Shielding (Zer/Inv)”.   

  1. You cannot reduce an LU if the Data Retention Utility is enabled and its properties are set to ”Read/Write”, or if the S-VOL is set to ”Setting Possible (Enabled)”, and mode to ”Unset”, and then reduce LUs.

  2. You must wait until after the drive is restored to reduce the LUs if the dynamic sparing/correction copy/copy back is in progress.

Changing LU Capacity   (back to top)

CAUTION: Before beginning any LUN expansion procedure, observe the following:

  • Do not skip any steps and make sure that you follow the on-screen instructions carefully. If you do not execute a procedure correctly, data in the array can be lost and the unified logical unit will not be created.

  • Back up the unified logical units before modifying them.

  • Format the unified logical units to delete the volume label which the operating system adds to logical units.

  • Create unified logical units only from logical units within the same array.

  • You must format a logical unit that is undefined before you can use it.

 

To change the logical unit capacity:

  1. From the array tree, click Groups > RAID Groups. The Raid Groups window is displayed.

  2. Click the Logical Units tab.

  3. Check the LUN on which you want to change capacity.

  4. Click Change LU Capacity. The Change Logical Unit Capacity is displayed. The current properties of the selected LUN are displayed, including:

  5. LUN

  6. Current Capacity

  7. Free space

  1. From the Basic tab, choose the desired operation to expand or shrink capacity:

  2. To expand or shrink the LUN capacity:

  1. Click Input and enter the capacity value you want.  ALL is the default selected from drag-down list, set the maximum available capacity.  

  2. To set available capacity from automatically, go to the step 6.  

  3. If you are setting the capacity manually, go to step 7.

  1. Click Add logical units and select a LUN or LUNs from the Available Logical Units table.  

  2. Go to step 6.

  1. To separate LUN expansion:

  1. Select either Separate last logical units or Separate all logical units  and check the desired box on the Available Logical Units table.  

  2. Go to step 7.

  1. Click the Input Capacity Options tab. Select Set Manually and check the desired box from the Free Space table. If you set the LUN of a created logical unit, add the LUN to this field. The LUN assignment numbers are in descending order.

  2. Click OK and the result dialog is displayed.  

  3. Click Close.

  4. Confirm your changes.

See Also   (back to top)

The following topics within this help system provide information that may be helpful in understanding the information on this page, and/or may provide additional information that is related, but not required to understand this topic.

   Creating RAID Groups

   Expanding Raid Groups

   Create and Map Volume Wizard

 

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