Migrating data to Thin Image Advanced-compatible volumes using Volume Migration

Thin Image Advanced User Guide

Version

9.8.6

Audience

anonymous

Part Number

MK-98RD9033-00

Volume Migration allows you to move data to a DRS-VOL (change the LDEV type of the source volume) without stopping the host operations. Before moving data, create a DRS-VOL (destination volume for the data). If the existing volume is a DP-VOL, create the DRS-VOL in a DP pool that is different from the one containing the existing volume. Specify the existing volume as the source volume and the new DRS-VOL as the target volume. Then use Volume Migration to move data.

Note the following when you perform this method.

If you specify a Dynamic Provisioning V-VOL as the source volume, you cannot specify the DRS-VOL created in the DP pool containing the source volume as the target volume.
You do not need to delete TrueCopy, Universal Replicator, global-active device, and ShadowImage pairs. You can change the LDEV type of the P-VOL or S-VOL of a TrueCopy, Universal Replicator, global-active device, or ShadowImage pair to DRS-VOL while keeping the pair without shutting down the host. For details about the pair status or pair configuration conditions that allow Volume Migration operations, see the Hitachi Volume Migration User Guide.

You must have the Storage Administrator (Provisioning) role and Storage Administrator (Local Copy) role.
Delete Thin Image pairs that do not use DRS-VOLs before you run Volume Migration if you want to change the LDEV type of the P-VOLs or S-VOLs of the existing Thin Image pairs. Volume Migration cannot move the data in the P-VOLs or S-VOLs of Thin Image pairs to DRS-VOLs.
If the data source volume belongs to a TrueCopy, Universal Replicator, global-active device, or ShadowImage pair, the pair must be in the status that allows data migration using Volume Migration.
Prepare a DP pool where you create a DRS-VOL to be used as the destination for data. If the source volume is a DP-VOL, prepare a DP pool that is different from the one containing the source volume.

In the prepared data destination DP pool, create a DRS-VOL.
For the procedure, see Creating Thin Image Advanced-compatible volumes.
Define the path for the target volume.
For details about how to define a path, see the Provisioning Guide for your storage system.
If you want to change the LDEV type of a volume that belongs to a Thin Image pair, delete the pair.
Define the Volume Migration pair in the configuration definition file.

In the command example for this procedure, group1 is defined as the group name and pair1 is defined as the name of the volume for the target pair.
Run Volume Migration by entering the paircreate command for the Volume Migration pair in SMPL status.
Command example:
```
paircreate -g group1 -d pair1 -m cc -vl
```
When the data starts to move to the target volume, the status of the Volume Migration pair changes to COPY.
Check that the operation of Volume Migration has completed by entering the pairdisplay command to check the pair status.
Command example:
```
pairdisplay -g group1 -fe
Group ... Seq#,LDEV#.P/S,Status, Seq#,P-LDEV# M CTG CM EM E-Seq# E-LDEV#
group1 ... 62496 18.P VOL PSUS,62496 19 - - C V 30053 30
group1 ... 62496 19.S VOL SSUS,----- 18 - - C - - -
```
When the data is successfully moved to the target volume, the status of the Volume Migration pair changes to PSUS. If the data fails to move to the target volume, the pair status changes to PSUE.
When the status of the Volume Migration pair changes to PSUS or PSUE, enter the pairsplit command and restore the pair status to SMPL.
Command example:
```
pairsplit -S -g group1 -d pair1
```
If the status of the Volume Migration pair changes to PSUE and the data fails to move to the target volume in step 6, repeat steps 5 through 7.
If an alert message is displayed, check it, and correct the problem. Then repeat steps 5 through 7.
Delete the source volume that is no longer necessary.