Skip to main content
Close
Hitachi Vantara Knowledge

Mapping logical volumes to hosts

  1. Last updated
  2. Save as PDF
Parent Topic
Child Topics

Configure LU paths workflow
  • Define LU paths.
  • Set a UUID, if desired.
  • Define alternate LU paths.
Parent Topic

Correspondence table for defining devices

When configuring the storage system, you will need definition information about devices set by LUN Manager, for example, LUs, LDKC:CU:LDEV, or UUID. A correspondence table similar to the example below is useful and recommended when collecting this information.

Port

LU

LDKC:CU:LDEV

UUID

OpenVMS device file name

BR

0000

00:00:30

148

$1$dga148

BR

0001

00:00:31

149

$1$dga149

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

Parent Topic

Defining LU paths

In a Fibre Channel or iSCSI environment, you must define LU paths and associate host groups or iSCSI targets with logical volumes. For example, if you associate a host group or an iSCSI target consisting of three hosts with logical volumes, LU paths are defined between the three hosts and the logical volumes.

Before you begin

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

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Ports/Host Groups/iSCSI Targets, and select the target host group or iSCSI target.

  3. Click Add LUN Paths.

  4. In the Add LUN Paths window, select the desired LDEVs from the Available LDEVs table, and then click Add.

    Selected LDEVs are listed in the Selected LDEVs table.

  5. Click Next.

  6. In Selection Object, click Fibre.

  7. Select the desired host groups from the Available Host Groups or Available iSCSI Targets table, and then click Add.

    Selected host groups are listed in the Selected Host Groups or Available iSCSI Targets table.

  8. Click Next.

  9. Confirm the defined LU paths.

    If the LDEV name or the LUN ID is edited, perform the following:
    1. Select the checkboxes of LDEV IDs that you want to change.
    2. Click Change LDEV Settings.
    3. In the Change LDEV Settings window, specify values in Prefix and Initial Number.
    4. Click OK.
    To change the LUN ID, perform the following:
    1. In the LUN ID column (Any number Sets of Paths), select the host groups (iSCSI Targets) checkboxes.
    2. Select the checkbox of the LDEV ID that you want to change.
    3. Click Change LUN IDs.
    4. In the Change LUN IDs window, specify the value in Initial LUN ID.
    5. Click OK.

  10. Click Finish.

    The Confirm window appears.

  11. 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.

  12. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.
Parent Topic

Setting a UUID

You can set an arbitrary ID to identify a logical volume from the host when host mode option 33 is set to on. The ID is referred to as the UUID (universally unique identifier) and is typically composed of a Prefix and an Initial Number.

Note the following when setting a UUID:

  • If host mode 05 OpenVMS is used with host mode option 33 set to ON, LUs that do not have UUID settings are inaccessible.
  • If host mode 05 OpenVMS is used with host mode option 33 set to OFF, LUs that have UUID settings are inaccessible.

The following rules apply to setting a UUID:

  • These characters cannot be used for UUID: \ / : , ; * ? " < > |
  • A space character cannot be used as the first or the last character of a UUID.
  • UUID is case-sensitive. For example, Abc and abc are different UUIDs.

To keep track of device information, create a correspondence table similar to the example in Correspondence table for defining devices.

Before you begin

  • The Storage Administrator (Provisioning) role is required to perform this task.
  • Before editing UUID settings, review the information about UUID requirements.

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Ports/Host Groups/iSCSI Targets.

  3. In the Host Groups/iSCSI Targets tab, click the link of the Port ID of the host group.

  4. Click the link of a Host Group Name.

  5. Click the LUNs tab.

  6. Select one or more logical units to which volumes are assigned (if a volume is assigned to an LU, the columns on the right of the LUN column are not empty).

    When multiple LUs are selected, the same UUID is set to all selected LUs.

  7. Click More Actions, and then select Edit UUIDs.

  8. In the Edit UUIDs window, in Prefix, type the UUID.

    If a UUID is already specified, you can change it. The UUID before changing appears in UUID in the Edit UUIDs window. However, if multiple LUs, or N/As are selected, the Prefix box is blank.

    For an OpenVMS server host, enter a UUID composed of a Prefix and an Initial Number. The Prefix may include up to 5 digits, from 1 to 32767, and the Initial Number may include up to 5 digits, from 0 to 32767.

    For a server host other than OpenVMS, enter a UUID composed of a Prefix and an Initial Number. The Prefix may include up to 64 ASCII characters (letters, numerals and symbols) and the Initial Number may include up to 9 digits.

    When changing the server host OS from HP-UX to OpenVMS, or from OpenVMS to HP-UX, the same UUID cannot be used continuously. Clear the UUID setting (see Clearing a UUID setting), and then set the proper UUID for a server host.

  9. To sequentially number the UUIDs, type the first digit in the Initial Number box. The following rules apply to the Initial Number: 

    1: Up to 9 numbers are added (1, 2, 3, ... 9).
08: Up to 92 numbers are added (08, 09, 10, ... 99).
If the host mode is set to OpenVMS, the numbers are as follows:
8, 9, 10, ... 99
23: Up to 77 numbers are added (23, 24, 25, ... 99).

  10. Click Finish.

    The Confirm window appears.

  11. 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.

  12. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.
Parent Topic
Child Topics

UUID requirements

A UUID (user-definable LUN identifier) is typically composed of a Prefix and an Initial Number.

The following rules apply to defining a UUID:

  • These characters cannot be used for a UUID: \ / : , ; * ? " < > |
  • A space character cannot be used as the first or the last character of a UUID.
  • UUIDs are case-sensitive. For example, Abc and abc are different UUIDs.

Also note the following when defining a UUID:

  • If host mode 05 OpenVMS is used with host mode option 33 set to ON, LUs that do not have UUID settings are inaccessible.
  • If host mode 05 OpenVMS is used with host mode option 33 set to OFF, LUs that have UUID settings are inaccessible.
  • For an OpenVMS server host, the Prefix can include up to 5 digits, from 1 to 32767, and the Initial Number can include up to 5 digits, from 0 to 32767.
  • For a server host other than OpenVMS, the Prefix can include up to 64 ASCII characters (letters, numerals and symbols) and the Initial Number can include up to 9 digits.
Parent Topic

Defining alternate LU paths

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

You may want to define alternate LU paths so that if one LU path fails, you will be able to switch to its alternate path.

To create an alternate LU path, copy the original LU path from one port to another. For example, if you want to define an alternate for the LU path from the CL1-A port to logical volume 00:00:01, copy the LU path from the CL1-A port to another port.

Use one of these methods to copy LU paths:

  • Copy all the LU paths defined in a host group or an iSCSI target
  • Copy one or more (but not all) LU paths defined in a host group or an iSCSI target

Before taking the following steps:

Parent Topic
Child Topics

Copying all LU paths defined in a host group

Use this procedure to copy all LU paths defined in a host group.

Before you begin

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

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Expand the target host group and click Ports/Host Groups/iSCSI Targets.

  3. In the Host Groups pane, select the Port ID of a host group.

  4. Click More Actions and select Create Alternative LUN Paths.

  5. In the Create Alternative LUN Paths window, select the copy destination port from the Available Ports table, and then click Add.

    The selected ports appear in the Selected Ports table.

  6. Click Finish.

    The Confirm window appears.

  7. 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.

  8. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.

Parent Topic

Copying all LU paths defined in an iSCSI target

Use this procedure to copy all LU paths defined in a host group.

Before you begin

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

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Expand the target host group, and click Ports/Host Groups/iSCSI Targets.

  3. In the iSCSI Targets pane, select the Port ID of a iSCSI target.

  4. Click More Actions and select Create Alternative LUN Paths.

  5. In the Create Alternative LUN Paths window, select the copy destination port from the Selected Ports table, and then click Add.

    The selected ports appear in the Selected Ports table.

  6. Click Finish.

    The Confirm window appears.

  7. 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.

  8. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.

Parent Topic

Copying selected (but not all) LU paths defined in a host group
You can use this procedure to copy the LU paths associated with a selected host group.

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Ports/Host Groups/iSCSI Targets.

  3. In the Host Groups/iSCSI Targets tab, click the link of the Port ID of the host group.

  4. Click the link of a Host Group Name.

  5. Click LUNs tab.

  6. Select one or more logical units to which volumes are assigned (if a volume is assigned to a logical unit, the columns on the right of the LUN column are not empty).

  7. Select Copy LUN Paths.

  8. In the Copy LUN Paths window, select the host group to which you want to paste paths from the Available Host Groups table, and then click Add.

    The selected host groups appear in the Selected Host Groups table.

  9. Click Finish.

    The Confirm window appears.

  10. 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.

  11. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.
Parent Topic

Copying selected (but not all) LU paths defined in an iSCSI target

You can use this procedure to copy the LU paths associated with a selected host group.

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Ports/Host Groups/iSCSI Targets.

  3. In the Host Groups/iSCSI Targets tab, click the link of the Port ID of the iSCSI target.

  4. Click the link of a iSCSI target.

  5. Click LUNs tab.

  6. Select one or more logical units to which volumes are assigned (if a volume is assigned to a logical unit, the columns on the right of the LUN column are not empty).

  7. Select Copy LUN Paths.

  8. In the Copy LUN Paths window, select the iSCSI target to which you want to paste paths from the Available iSCSI Targets table, and then click Add.

    The selected host groups appear in the Selected iSCSI Targets table.

  9. Click Finish.

    The Confirm window appears.

  10. 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.

  11. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.
Parent Topic

Viewing LU path settings

Before you begin

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

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Ports/Host Groups/iSCSI Targets.

  3. Click the link of a host group or iSCSI target.

  4. Select the LUNs tab.

  5. Select a LUN ID to open the LUN Properties window.

Parent Topic

Clearing a UUID setting

You can clear the UUID setting that has been set to identify a logical volume from the host.

Before you begin

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

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Logical Devices.

  3. In the LDEVs pane of the Logical Devices window, click Create LDEVs.

  4. Select the LDEVs with the UUID setting you want to clear.

  5. Select Delete UUIDs. The Delete UUIDs window opens.

  6. Click Finish.

    The Confirm window appears.

  7. 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.

  8. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.

Parent Topic

Deleting LU paths

Before you begin

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

CautionDo not delete LU paths when host I/O is in progress.

Procedure

  1. Click Storage Systems, and then expand the Storage Systems tree.

  2. Click Ports/Host Groups/iSCSI Targets.

  3. Click the link of a host group.

  4. Select the LUNs tab.

  5. Select the LU path you want to delete.

    CautionWhen an LDEV is selected and Delete LUN Paths is performed, all LUN paths of the selected LDEV are deleted by default.

  6. Click More Actions and select Delete LUN Paths.

  7. In the Delete LUN Paths window, confirm that the LU paths that you want to delete are listed in Selected LUN Paths.

    If LU paths that you do not want to delete are listed, select the LU path you do not want to delete, and then click Remove from Delete process.
    CautionWhen an LDEV is selected and Delete LUN Paths is performed, all LUN paths of the selected LDEV are deleted by default.

  8. If necessary, check the Delete all defined LUN paths to above LDEVs check box. When checked, all additional LU paths on the selected LDEVs will be deleted.

  9. Click Finish to open the Confirm window.

    If you want to start shredding operations to delete the data of the volume, click Next. For detailed information about shredding operations, see the Hitachi Volume Shredder User Guide.

  10. Click Finish.

    The Confirm window appears.

  11. 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.

  12. Click Apply.

    If the Go to tasks window for status check box is selected, the Tasks window appears.

    If you delete many paths at one time, the deletion process may take time and the dialog box may seem to hang temporarily.
Parent Topic

Next steps

Configure CHAP users to ensure only authorized hosts can access the storage resources.

Parent Topic