LUN Expansion

This help page provides information to guide you through the procedure to increase the size of an existing logical unit on the storage array by adding one or more existing logical units to it. It also includes procedures to remove logical units that have been added. This help page contains the following topics:

Overview (back to top)

The LUN expansion feature provides the capability of combining two or more existing logical units into a single unit. The procedure includes designating a main logical unit and then adding other ("sub") logical units to it. The expanded LUN is called a unified logical unit.

LUN expansion can be reversed by removing the last logical unit combined with the main logical unit. The unified logical unit can also be separated back into the original logical units. The procedures for expanding or contracting a logic unit are included below.

CAUTION: Before beginning any LUN expansion procedure please read and follow all of the following instructions.

Do not skip any steps and make sure that you follow the 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.

Displaying Unified Logical Unit Properties (back to top)

To display the list of unified logical units:

In the Arrays window, select the array whose date and time you want to update, and either click Show and Configure Array, or double click the name of the array. The Array window and the Explorer tree are displayed.
In the Explorer tree, expand the Settings menu to show the list of available functions.
In the expanded menu, select LUN Expansion. The LUN Expansion window is displayed. It shows the list of unified logical units in the array and the following parameters for each listed unit:

Item	Description
LUN	This shows the name of the unified logical unit.
Capacity	This shows the size in GB of the unified logical unit..
RAID Group	This shows the name of the RAID group that the unified logical unit is part of.
RAID Level	This shows the RAID level of the unified logical unit. This is RAID6.
TYPE	This shows the type of hard drive the logical unit resides on: SATA or SAS.
Status	This shows the status of the unified logical unit: Normal or Alarm.

Creating a Unified Logical Unit (back to top)

To create a unified logical unit:

In the LUN Expansion window, click Create Unified LU. The Create Unified Logical Unit dialog box is displayed. It shows the list of main and sub logical units that are available to create unified logical units.
In the Create Unified Logical Unit dialog box, select the main logical and sub units and click OK. A warning message is regarding the mismatch of RAID levels and hard drive types displayed.
To create the designated unified logical unit, click the to agree that you have read the warning, and then click Confirm. Navigator 2 creates the designated unified logical unit and displays a confirmation message that the unit has been created, and then displays the LUN Expansion window as described above.
Click Close to exit the message box and return to the LUN Expansion window.
Observe the LUN Expansion window and verify that the designated unified logical unit is listed correctly.

Modifying a Unified Logical Unit (back to top)

To modify a unified logical unit:

Click the name of the unified logical unit. The LUN Expansion window is replaced with a window that displays the properties of the selected unified logic unit and the sub unit(s) it contains. The properties are described in the table above. In addition to the properties tables, the window contains the following function buttons:
Add LUs
Separate Last LU
Separate All LUs

Click the function button needed to accomplish the desired task. Each button displays a dialog box for the selected function. In addition to the information below, the dialog box for each function has its own help page.

Add LUs (back to top)

To add a logical unit to a unified logical unit:

In the unified logical unit properties window, click Add LUs. The add Logical Units dialog box is displayed. The dialog box includes a table that displays the parameters of the selected unified logical unit, and a table that lists the available logical units that can be added to the existing unified logical unit.
Click the to the left of the name of the LUN that you want to add to the unified logical unit.
Click OK. A warning message regarding RAID levels and drive types is displayed. The warning message also includes information that the data in the logical unit that is added will be destroyed.
To add the selected logical unit to the unified logical unit, click the to agree that you have read the warning message, and then click Confirm. A message box confirming that the logical unit has been added is displayed.
Click Close to exit the message box and return to the unified logical unit properties window.
Observe the contents of the window and verify that the logical unit has been added.

Separate Last LU (back to top)

This process is the reverse of adding a logical unit to a unified logical unit. To remove the last logical unit that was added to a unified logical unit:

In the Arrays window, select the array whose date and time you want to update, and either click Show and Configure Array, or double click the name of the array. The Array window and the Explorer tree are displayed.
In the Explorer tree, expand the Settings menu to show the list of available functions.
In the expanded menu, select LUN Expansion. The LUN Expansion window is displayed. It shows the list of unified logical units in the array and a set of parameters for each listed unit.
In the LUN Expansion window, click the LUN that you want to separate.
In the unified logical unit property window, click Separate Last LUs. A confirmation dialog box is displayed.
In the confirmation dialog box, click the to agree that you have read the warning message, and then click Confirm. A message box stating that the logical unit has been successfully separated is displayed.
Click Close to exit the message box and return to the unified logical unit properties window.
Observe the contents of the window and verify that the logical unit was separated from the unified logical unit.

Separate All LUs (back to top)

To separate a unified logical unit into the original logical units that were used to create it:

In the Arrays window, select the array whose date and time you want to update, and either click Show and Configure Array, or double click the name of the array. The Array window and the Explorer tree are displayed.
In the Explorer tree, expand the Settings menu to show the list of available functions.
In the expanded menu, select LUN Expansion. The LUN Expansion window is displayed. It shows the list of unified logical units in the array and a set of parameters for each listed unit.
In the LUN Expansion window, click the LUN that you want to separate.
In the unified logical unit property window, click Separate All LUs. A confirmation dialog box is displayed.
In the confirmation dialog box, click the to agree that you have read the warning message, and then click Confirm.
Click Close to exit the message box and return to the unified logical unit properties window.
Observe the contents of the window and verify that the logical unit was separated from the unified logical unit.