Home > Storage > PowerMax and VMAX > Storage Admin > Dell PowerMax and VMAX: Non-Disruptive and Minimally Disruptive Migration Best Practices and Operational Guide > Create phase changes
This section describes the changes and new requirements in the create phase of an O-MDM migration.
The administrator must now identify the source WWNs, target array ID, and existing target array initiator group. The source WWNs are a list of hexadecimal WWNs. These WWNs can be verified using the ‘symsan’ CLI command.
Example contents of an 8 WWN source file: omdm_8wwn.txt:
60000970000197802041533030433742
60000970000197802041533030433743
60000970000197802041533030433744
60000970000197802041533030453941
60000970000197802041533030453942
60000970000197802041533030453943
60000970000197802041533030453944
60000970000197802041533030453945
This list may be created and verified from the following symsan command as an example:
symsan list -sid 721 -sanluns -wwn 50000973A81FE449 -dir all -p all
Symmetrix ID: 000197801721
Remote Port WWN: 50000973A81FE449
ST
A
T Flags Block Capacity LUN Dev LUN
DIR:P E ICR THS Size (MB) Num Num W WWN
------ -- ------- ----- -------- ----- ----- - --------------------------------
02D:11 RW ... FXX 512 187500 38 00C7B X 60000970000197802044533030433742
02D:11 RW ... FXX 512 187500 39 00C7C X 60000970000197802044533030433743
02D:11 RW ... FXX 512 187500 3A 00C7D X 60000970000197802044533030433744
02D:11 RW ... FXX 512 187500 3B 00E9A X 60000970000197802044533030453941
02D:11 RW ... FXX 512 187500 3C 00E9B X 60000970000197802044533030453942
02D:11 RW ... FXX 512 187500 3D 00E9C X 60000970000197802044533030453943
02D:11 RW ... FXX 512 187500 3E 00E9D X 60000970000197802044533030453944
02D:11 RW ... FXX 512 187500 3F 00E9E X 60000970000197802044533030453945
Similarly, the Unsphere 10.0 interface allow you to select donor devices from the WWNs that are available to the array:
The ‘create’ command first verifies that the requirements and restrictions are met to ensure that the migration can proceed and verifies that the target array has sufficient resources available to duplicate the application’s storage. The application’s storage configuration is then copied to the target array, creating equivalently provisioned devices. ORS activate (data copy) does not start until the following cutover action occurs.
When creating the storage configuration on the target array:
Example of a Unisphere 10.0 create dialog after the donor device WWNs have been chosen:
After the application’s storage configuration has been duplicated on the target array, the create operation concludes by connecting source-side devices with the corresponding target-side devices through a DM replication pathway and starts the data migration. The migration will immediately enter the CutoverReady state. The administrator must shut down the application before a Cutover operation can be issued. A ‘cancel’ command can be used to cancel the migration and undo the target-side storage provisioning done by the create operation.
If the create action fails:
(or)
The following command creates an Open Data Migration (O-MDM) session. The following is displayed when the ‘symdm create -san’ command is issued:
symdm create –san -offline –file src_wwn_list.fil –tgt_sid 644 –tgt_sg APP1
–tgt_ig APP1_INIT_GRP
A DM 'Offline SAN Create' operation is
in progress for storage group 'APP1'. Please wait...
Analyze Configuration...................................................Started.
Source Array:APM00150519204
Target Array:000197900644
Analyze Configuration...................................................Done.
Creating Device(s)........................................................Started.
Creating Device(s) on Target........................................Done.
Update target SG Device(s)..........................................Started.
Update target SG Device(s)..........................................Done.
Create Storage Group(s) on Target..............................Started.
Create Storage Group(s) on Target..............................Done.
Create Port Group(s) on Target....................................Started.
Create Port Group(s) on Target....................................Done.
Start Data Replication...................................................Started.
Start Data Replication...................................................Done.
The DM 'Offline Create' operation successfully executed for
storage group 'APP1'.