Dell EMC Metro node 7.1 Administrator Guide

Starting a one-time device migration

1. Use the drill down command to display the components of the source of a view, virtual volume, or device, down to the storage volume level:

   VPlexcli:/clusters/cluster-1> drill-down –o virtual-volumes/Symm1254_7B7_1_vol
   virtual-volume: Symm1254_7B7_1_vol (cluster-1)
      local-device: Symm1254_7B7_1 (cluster-1)
         extent: extent_Symm1254_7B7_1
            storage-volume: Symm1254_7B7

2. Identify the device used by the source storage volume.
3. Use the 
ll /clusters/cluster-*/devices command to display available devices.
4. Identify an unused device as the destination.
5. Navigate to the appropriate migration context.

   For device migrations, navigate to device-migration context:

   VPlexcli:/> cd data-migrations/device-migrations

6. Use the dm migration start command to start a migration.

   Specify the --to device by name if that name is unique in the global namespace. Otherwise, specify a full pathname.

   For example:

   VPlexcli:/data-migrations/device-migrations> dm migration start --name migrate_012 --from device_012 --to device_012a --transfer-size 12M

   CAUTION:Setting a large a transfer size may result in data unavailability. Vary from the default only when performance implications are fully understood.

   If host I/O activity is high, setting a large transfer size may impact host I/O.

   See About transfer-size.