Creating LDEVs

The Storage Administrator (Provisioning) role is required to perform this task.

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 creating an LDEV in a selected storage system, free space can need to be created. Before volumes are deleted to create free space, remove the LU paths to the open-system volumes. For instructions on removing LU paths, see Deleting LU paths.

 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 wizard. Confirm the number of free spaces, then create the LDEVs accordingly.

For example, if you are creating LDEVs in parity group PG1-1 that 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, make sure the number of free spaces displayed on the Select Free Spaces window in the Create LDEVs window.

To create an LDEV:

 The T10 PI attribute can be defined only during the initial creation of LDEVs. The defined attribute cannot be removed from LDEVs on which the T10 PI mode is already set.

1. Perform one of the following to display the Create LDEVs window.

For Command Suite:

• On the Resource tab, expand the Storage Systems tree. Right-click Parity Groups of the target storage system, then select System GUI. On the LDEVs tab, select Create LDEVs.

For the General Tasks pane in Storage Navigator:

• On the General Tasks pane, select Create LDEVs.

For the Parity Groups window in Storage Navigator:

• Expand the Storage Systems tree and select Parity Groups. On the Parity Groups tab, click Create LDEVs.

• Expand the Storage Systems tree and select Parity Groups > Internal or External >. On the LDEVs tab, click Create LDEVs.

• Expand the Storage Systems tree and select Parity Groups. Click Actions > Logical Device > Create LDEVs to open the window.

For the Logical Devices window in Storage Navigator:

• Expand the Storage Systems tree and select Logical Devices. On the LDEVs tab, click Create LDEVs.

• Expand the Storage Systems tree and select Logical Devices. Click Actions > Logical Device > Create LDEVs to open the window.

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

• If creating internal volumes, select Basic.

• If creating external volumes, select External.

3. If creating an internal volume, select the parity group and 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, 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, then click Close.

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

4. Otherwise, if creating an external volume, select the external volume, 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, 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, then click Close.

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

5. To offset the specified LDEV capacity by boundary, set the Offset Boundary to ON.

Offset boundary is set to OFF by default.

6. 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 a number with two digits after the decimal point. You can change the capacity unit from the list.

7. 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.

 If creating of LDEVs in the free space of the accelerated compression-enabled parity group, estimate the LDEV capacity and the number of LDEVs. For details, see Guidelines for creating a pool when accelerated compression is used

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

1. In Prefix, type the characters that iscome 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.

9. 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 the accelerated compression-enabled parity group, 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 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 can be affected. For details, see Quick Format function.

10. Click Options to show more options.

11. 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 can be already in use, or already assigned to another emulation group (group by 32 LDEV numbers).

2. Click Close.

12. In the Create LDEVs window, from the MP Unit list, select an 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.

13. In T10 PI, select Enable or Disable.

14. Click Add.

The created LDEVs 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.

15. If necessary, change the following LDEV settings:

• Click Change LDEV Settings to open the Change LDEV Settings window. For details about how to change the LDEV settings, see Changing LDEV settings.

16. If necessary, delete an LDEV from the Selected LDEVs table.

Select an LDEV to delete, then click Remove. For details about how to remove an LDEV, see Removing an LDEV to be registered.

17. Click Finish.

The Confirm window opens.

To continue the operation for setting the LU path and defining a logical unit, click Next. For details about how to set the LU path, see Defining LU paths .

18. In the Confirm window, confirm the settings, in Task Name type a unique name for this task or accept the default, then click Apply.

If Go to tasks window for status is checked, the Tasks window opens.