Creating an LDEV

Use this procedure to create one or more internal or external logical volumes (LDEVs) in a selected storage system. You can create multiple LDEVs at once, for example, when you are setting up your storage system. After the storage system is set up, you can add LDEVs as needed.

Before you can create an LDEV in a storage system, you might need to create free space. Before deleting volumes to create free space, remove the LU paths to the open-system volumes.

Before you begin

  • The Storage Administrator (Provisioning) role is required to perform this task.
  • You can create LDEVs using any of the following tabs in Hitachi Device Manager - Storage Navigator:
    • Parity Groups tab when selecting Parity Groups.

      You can create multiple LDEVs in the specified free space by setting the necessary items collectively. If multiple free spaces are in one parity group, the number of free spaces appears in Total Selected Free Space in the Parity Group Selection section on the Create LDEVs window. Confirm the number of free spaces, and then create the LDEVs accordingly.

      For example, if you are creating LDEVs in parity group PG1-1 and it contains two free spaces, 2 appears in Total Selected Free Space. In this case, if you specify 1 in Number of LDEVs per Free Space, and continue to create the LDEV, two LDEVs are created because one LDEV is created for each free space.

      When you select parity groups in the Parity Groups window or the Internal/External window, and open the Create LDEVs window, all free spaces in the parity groups are selected in the initial setting of the Select Free Spaces window. When you select the interleaved (concatenated) parity group in the Parity Groups window or the Internal/External window, and open the Create LDEVs window, all free spaces in every parity groups are selected in the initial setting of the Select Free Spaces window.

      In this case, if LDEVs are created by the initial setting without confirming the number of free spaces, more LDEVs than necessary can be created. When you create LDEVs, confirm the number of free spaces displayed on the Select Free Spaces window in the Create LDEVs window

    • LDEVs tab when selecting any parity group in Parity Groups.
    • LDEVs tab when selecting Logical Devices.

Procedure

  1. In the Device Manager - Storage Navigator Explorer pane, click Storage Systems, expand the target storage system, and then click Logical Devices.

  2. In the LDEVs tab, click Create LDEVs.

  3. In the Create LDEVs window, from the Provisioning Type list, select the provisioning type for the LDEV to be created.

  4. If creating an internal volume, select the parity group, and then do the following:

    1. From the Drive Type/RPM list in Parity Group Selection, select the drive type and RPM.

    2. From the RAID level list in Parity Group Selection, select the RAID level.

    3. Click Select Free Spaces.

    4. In the Select Free Spaces window, in the Available Free Spaces table, select the free spaces to be assigned to the volumes.

      Do the following, if necessary:

      - To specify the conditions and show the free space, click Filter, specify the conditions, and then click Apply.

      - To specify the unit for capacity and the number of rows to view, click Options.

    5. Click View Physical Location.

    6. In the View Physical Location window, confirm where the selected free space is physically located, and then click Close.

    7. In the Select Free Spaces window, if the selected free spaces have no issues, click OK.

  5. Otherwise, if creating an external volume, select the external volume, and then do the following:

    1. Click Select Free Spaces.

    2. In the Select Free Spaces window, in the Available Free Spaces table, select the free space to be assigned to the volumes.

      Do the following, if necessary:

      - To specify the conditions and show the free space, click Filter, specify the conditions, and then click Apply.

      - To specify the unit for capacity and the number of rows to view, click Options.

    3. Click View Physical Location.

    4. In the View Physical Location window, confirm where the selected free space is physically located, and then click Close.

    5. In the Select Free Spaces window, if the selected free spaces have no issues, click OK.

  6. If you want to offset the specified LDEV capacity by boundary, set the Capacity Compatibility Mode (Offset boundary) to ON. Capacity Compatibility Mode (Offset boundary) is set to OFF by default.

  7. In LDEV Capacity, type the amount of LDEV capacity to be created and select a capacity unit from the list.

    Enter the capacity within the range of figures displayed below the text box. You can enter the number with 2 digits after decimal point. You can change the capacity unit from the list.

  8. In Number of LDEVs, type the number of LDEVs to be created.

    • If you create internal volume, Number of LDEVs per Free Space appears.
    • If you create external volume, Number of LDEVs per External Volume appears.
    Caution

    If creating LDEVs in the free space of the parity group with accelerated compression enabled, estimate the LDEV capacity and the number of LDEVs.

  9. In LDEV Name, specify a name for this LDEV.

    1. In Prefix, type the characters that will become the fixed characters for the beginning of the LDEV name. The characters are case-sensitive.

    2. In Initial Number, type the initial number that will follow the prefix name.

  10. In Format Type, select the format type for the LDEV from the list.

    • For an internal volume, select Normal Format, Quick Format, Parity Group Format, or No Format. For LDEVs in a parity group with Accelerated Compression enabled, Quick Format cannot be selected.

      If No Format is selected, format the volume after creating LDEVs.

    • For an external volume, if you create the LDEV, select Normal Format or No Format.

      If the external volume can be used as it is, select No Format. The created LDEV can be used without formatting.

      If the external volume needs to be formatted, select No Format and then format the volume with the external storage system, or select Normal Format.

    • If Quick Format is selected while quick formatting is in progress, host I/Os may be affected. For details, see Quick Format function

  11. Click Options to show more options.

  12. In Initial LDEV ID, make sure that an LDEV ID is set. To confirm the used number and unavailable number, click View LDEV IDs to open the View LDEV IDs window.

    1. In Initial LDEV ID in the Create LDEVs window, click View LDEV IDs.

      In the View LDEV IDs window, the matrix vertical scale represents the second-to-last digit of the LDEV number, and the horizontal scale represents the last digit of the LDEV number. The LDEV IDs table shows the available, used, and disabled LDEV IDs.

      In the table, used LDEV numbers appear in blue, unavailable numbers appear in gray, and unused numbers appear in white. LDEV numbers that are unavailable may be already in use, or already assigned to another emulation group (group by 32 LDEV numbers).

    2. Click Close.

  13. In the Create LDEVs window, from the MP Unit list, select a MP unit to be used by the LDEVs.

    • If you assign a specific MP unit, select the ID of the MP unit.
    • If you can assign any MP unit, click Auto.

  14. In T10 PI, select Enable or Disable.

    The T10 PI attribute can be specified when creating a Basic volume of emulation type OPEN-V.
    CautionThe T10 PI attribute can only be defined during the initial creation of LDEVs. The defined attribute cannot be removed from LDEVs on which it is already set.

  15. Click Add.

    The LDEVs to be created are added to the Selected LDEVs table.

    The Provisioning Type, Parity Group Selection, LDEV Capacity, and Number of LDEVs per Free Space or Number of LDEVs per External Volume fields must be set. If these required items are not registered, you cannot click Add.

  16. For the LDEVs in the Selected LDEVs table, you can change the following LDEV settings: LDEV name, initial LDEV ID, T10 PI, and MP unit.

  17. If you need to delete an LDEV from the Selected LDEVs table, select the LDEV, and then click Remove.

  18. When the information in the Selected LDEVs table is correct, click Finish.

    The Confirm window appears.

    To continue the operation for setting the LU path and defining a logical unit, click Next.

  19. In the Task Name text box, type a unique name for the task or accept the default.

    You can enter up to 32 ASCII characters and symbols, with the exception of: \ / : , ; * ? " < > |. The value "date-window name" is entered by default.

  20. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.
Related Tasks
Parent Topic
  • Create LDEV function

    Use the Create LDEV function of Virtual LUN to create a custom-size volume (CV).