Creating Universal Replicator pairs

When you create a pair, the initial copy operation copies all data on the P-VOL to the S-VOL. The P-VOL remains available to the host for I/O operations during the initial copy operation.

Prerequisites

• The initial copy must be performed from the primary system.

• S-VOLs must be offline to all hosts.

• The primary and secondary systems and remote paths must be defined.

• The P-VOL capacity and S-VOL capacity must be the same size (same number of blocks). To view the capacity in blocks, click Options > Capacity Unit > block in the Logical Devices window. If the capacity is displayed in GB or TB, a slight difference in P-VOL and S-VOL capacity might not be displayed.

• Journal volumes must be registered to the journals that are associated with pairs.

• When creating a UR delta resync pair, see Creating the delta resync pair and make sure all of the conditions are met.

• Make sure Performance Monitor is stopped.

• If you want to create multiple pairs at the same time, you must plan the S-VOLs ahead of time so that the system will assign the correct S-VOLs to the selected P-VOLs. When you select multiple volumes as P-VOLs, you will specify one S-VOL and the selection method (Interval or Relative Primary Volume) for determining the rest of the S-VOLs to assign to the selected P-VOLs. The system automatically assigns S-VOLs to the selected P-VOLs using the LUN IDs determined by the specified selection method.

• Interval: To use Interval, set up the S-VOL LUN IDs according to the interval between their LUN ID numbers. The system will skip the specified interval between LUN ID numbers when assigning S-VOLs. For example, if you specify LUN ID 01 as the Base Secondary Volume and specify 3 for Interval, LUN ID 04 (01+3) in the secondary system is assigned to the next P-VOL, LUN ID 07 (04 + 3) is assigned to the following P-VOL, and so on.

• Relative Primary Volume: To use Relative Primary Volume, set up the S-VOL LUN IDs according to the difference between the LUN ID numbers of the first selected P-VOL and the selected Base Secondary Volume. The difference between these two LUN ID numbers determines the LUN ID of the S-VOL for each P-VOL. For example, if the LUN IDs of the first three selected P-VOLs are 01, 05, and 06 and you set the LUN ID for the Base Secondary Volume to 02, the LUN IDs of the three S-VOLs will be 02, 06, and 07, respectively.

• Review the following points before beginning the procedure:

• You will select the volumes to be paired by port, GID, and LUN. Make sure to have this information available.

• You will assign master and restore journals to the P-VOL and S-VOL during the operation.

• You will assign a mirror ID to the pairs. This identifies the pairs within the journal. A mirror refers to the pair within the journal.

• If the mirror ID that you will assign to the new pair contains any pairs, the new pair’s volumes must belong to the same primary and secondary systems defined in the mirror.

Procedure

1. Open the Remote Replication window.

In Command Suite: On the Resources tab, expand the Storage Systems tree, right-click the target storage system, and click Remote Replication.

In Device Manager - Storage Navigator: In the Storage Systems tree, click Replication > Remote Replication.

2. Select the UR Pairs tab, and click Create UR Pairs.

3. For Remote Storage System, select the secondary system’s Model/Serial Number and Path Group ID.

• If the mirror contains an existing pair, the same Model/Serial Number as the existing pair must be selected.

4. In Primary Volume Selection, for Selection Object, select the port type for the local storage system.

5. In the Primary Volume Selection box, in LU Selection select the Port ID and Host Group Name or iSCSI Target Alias of the volumes that will become the P-VOLs of the new pairs. The Available LDEVs table only displays volumes that can be used as P-VOLs of UR pairs.

6. In the Primary Volume Selection box, in the Available LDEVs table select the volume that will become the P-VOL of the pair. You can select multiple volumes.

• When you specify a virtual storage machine volume, specify the physical LDEV ID in the storage system. You cannot specify the virtual LDEV ID.

• You must select data volumes in the same virtual storage machine. Volumes in different virtual storage machines cannot be registered to the same journal.

7. In the Secondary Volume Selection box, for Base Secondary Volume, select the Port ID, Host Group ID/iSCSI Target ID, and LUN ID for the volumes that will become the S-VOLs for the selected P-VOLs.

LUN IDs are displayed as hexadecimal numbers by default. For instructions on changing the LUN ID display to decimal, see the System Administrator Guide for Virtual Storage Platform Gx00 and Fx00 Models.

8. If you selected multiple primary volumes, for Selection Type select the method for assigning the S-VOLs, Interval or Relative Primary Volume. For details, see the Prerequisites above this procedure.

9. For Mirror Selection, specify the following:

1. For Master Journal, select a number from the list of registered journal IDs. The list excludes already-assigned master and restore journal IDs.

2. For Mirror ID, assign an identifier number for the mirror.

3. For Restore Journal, select a number from the list of registered journal IDs. All journal IDs display (000-0FF).

4. For CTG ID, select a consistency group from the list of those registered in the storage system. An asterisk indicates the CTG is assigned to a pair in the Select Pairs table.

Assign the same ID for the consistency group as the journal ID for UR.

10. Click Options to define the following optional settings:

1. For Initial Copy Type, specify whether to perform the initial copy operation to copy the P-VOL data to the S-VOL. Normally select Entire.

- Entire (default): Select Entire to establish the pair and copy all P-VOL data to the S-VOL.

- None: Select None to establish the pair without copying any data to the S-VOL. Use this option only when the P-VOL and S-VOL are already identical, or when the P-VOL and S-VOL do not yet contain any data (for example, new blank volumes).

- Delta: Select Delta only when creating a UR delta resync pair in the delta resync configuration.

2. For Initial Copy Priority, you can specify the scheduling order (1-256) for the initial copy operation. The default is 32.

If a timeout error occurs, the copy operation might not be executed in the order that you set with Initial Copy Priority. The timeout error can be caused by a CU configuration or remote copy path error. Review the error, release the pair with the error, and then retry the Paircreate operation.

3. In the Error Level list, specify the desired system response if a failure occurs during this operation:

Select Mirror to split all pairs in the failed pair’s mirror. Mirror is the default.

Select LU to split only the pair that failed.

11. Click Add to move the specified pair or pairs to the Selected Pairs table. Repeat the steps above as needed to add pairs with P-VOLs in other ports or host groups and S-VOLs in other ports or remote storage systems.

12. In the Selected Pairs table, review the P-VOL and S-VOL details carefully to make sure that the information for each pair is correct.

To change the settings for a pair, select the pair and click Change Settings. You can change the S-VOL and pair options, but you cannot change the P-VOL. If you need to change a P-VOL, select the pair and click Remove to remove the pair from the Selected Pairs table.

13. When the pair information in the Selected Pairs table is correct, click Finish.

14. In the Confirm window, review the settings and enter a task name in the Task Name box.

15. Click Apply to save your settings to the system.

Based on the initial copy type you selected, you can verify that the pair status is correct in the Remote Replication window as shown in the following table.

To monitor the progress of the operation, click File > Refresh in the menu bar. This updates the information in the list. You can also check the current pair status by using the View Pair Properties window. If you selected Entire for the initial copy type, the status will change from COPY to PAIR when the initial copy operation is complete.