Task 5: Create LUNs

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Applies To: Windows Server 2003 R2

After you complete tasks 1 through 4, you can use the Create LUN Wizard to create a LUN and optionally assign the LUN to a server or target.

To create and assign a LUN

  1. In LUN Management, click Create LUN.

  2. Follow the steps in the Create LUN Wizard, providing the information in Table 1.

Table 1   Completing the Create LUN Wizard

Wizard Page Details

Before You Begin

Before you create a LUN, verify that the following steps have been completed:

  • At least one subsystem is listed in the Subsystems node.

  • Storage space is available on at least one of the available subsystems.

  • If you want to use the wizard to assign the LUN to a server, the SAN server connections have been configured.

Subsystem and Type

Select the subsystem on which to create the LUN and specify the type of LUN to create.

  • The list of subsystems at the top specifies the total capacity of each available subsystem, the type of subsystem (Fibre Channel or iSCSI), and the percentage of free space.

  • The list of LUN types at the bottom includes each LUN type that is available on the selected subsystem and specifies the maximum-size LUN for each LUN.

  • Fault tolerant LUN types require more disk space than simple LUNs. Therefore, the maximum size of the LUN is smaller than for a simple LUN.

Size and Name

Type a name for the new LUN and specify the size of the LUN:

  • The LUN name can have as many as 63 characters.

  • Depending on the version of the VDS provider that the subsystem is running, you may not be able to type a name for the LUN.

  • Type the LUN size and click the drop-down list to select between megabytes (MB), gigabytes (GB) and terabytes (TB).

Target Access (iSCSI only)

If iSCSI targets have already been created on the subsystem, you can assign the LUN to one of those targets now. You can also leave it unassigned for later use.

Server Access

If you have already configured your server connections, you can assign the LUN to a server or cluster now. You can also leave it unassigned for later use.

noteNote
If you are creating a LUN on an iSCSI subsystem, then this LUN must also be assigned to an iSCSI target. The server or cluster you select on the Server Access page will only have access to the LUN after the iSCSI initiator on that server or cluster logs on to the target the LUN has been assigned to.

Create Volume (Fibre Channel only)

If on the Server Access page you chose to assign the LUN to the server you are currently managing with the Storage Manager for SANs snap-in, you can create an NTFS volume for the LUN. If you select to format the volume:

  • As a general rule, leave the Allocation unit size option as Default. The allocation unit size is the smallest amount of disk space that can be allocated to hold a file. Windows selects default sizes based on the size of the volume. These default sizes are selected to reduce the amount of space that is lost and the amount of fragmentation on the volume.

  • The Quick Format option speeds the volume creation process on large LUNs. If you want to scan for bad sectors during the formatting process, unselect this option and a full file format will be done.

Note

If you prefer, you can select not to format the volume and can use DiskPart to format it later. For more information, see DiskPart.

Create New LUN

Before creating the LUN, the wizard lists all the properties you have selected for the new LUN. Click Create LUN to start the LUN creation process.

Monitoring the status of LUN creation

The process of creating a LUN can take minutes or hours, depending on the size of the LUN. Do not close Storage Manager for SANs while a LUN is being created. If the session ends before the process completes, you might not be able to determine the completion status for the LUN.

To monitor the status of the LUN while it is being created, in the LUN Management node, refer to the Task Status column on the results pane. While the LUN is being created, the column shows the percentage of the LUN that has been completed. When the operation has finished successfully, the task status changes to Created.

If LUN creation fails, you can click the LUN entry in the results pane to display failure information in the description area below it.