Migrating data from a DS3200/DS3500 system by using SAS connections

Use this procedure to use SAS connections to migrate data from a DS3200 or DS3500 system to a Storwize® V3700 system. The management GUI System Migration wizard can also be used, and is launched by going to Pools > System Migration and clicking the Start New Migration tab. Guidance is provided on the wizard panels. The Need help link on a panel provides more details.

Before you begin

  1. Install and configure the system.
  2. Ensure that you have the required number of SAS HD to mini SAS cables.
    • Two cables for host attachment.
    • One of the following:
      • Four cables for DS3500 attachment
      • Two cables for DS3200 attachment
  3. Stop all host I/O operations.
  4. Unmap the logical drives that contain the data from the hosts.

Procedure

Hardware configuration

  1. Unplug the SAS cables between the DS3200/DS3500 and the hosts. Ensure that no SAS host ports on the DS3200/DS3500 system are occupied.
  2. Connect the DS3200/DS3500 SAS host ports to the Storwize V3700 SAS host ports, as shown in Figure 1 and Figure 2. Ensure that each DS3200/DS3500 controller is connected to both Storwize V3700 canisters. These connections provide extra redundancy and ensure that the detected MDisks are not degraded.
    Figure 1. Connecting SAS cables from Storwize V3700 to DS3200
    Diagram showing cable connections from Storwize V3700 to DS3200
    •  1  SAS host/controller ports
    •  2  SAS ports for host connectivity
    Figure 2. Connecting SAS cables from Storwize V3700 to DS3500
    Diagram showing cable connections from Storwize V3700 to DS3500
    •  1  SAS host/controller ports
    •  2  6 Gbps SAS ports for host connectivity
  3. Connect the remaining Storwize V3700 SAS host port to the host server SAS ports.

Software configuration

  1. On the DS3200/DS3500 system, use the Storage Manager to define a new host by using the detected SAS WWPNs from the Storwize V3700. Set the Host type (operating system) to IBM TS SAN VCE.
  2. To confirm the WWPNs of the SAS ports, enter the following command on the Storwize V3700 system.
    svinfo lsportsas
  3. On the DS3200/DS3500 system, use the Storage Manager to map a single logical drive to the newly created host as a logical unit.
    Note: If you have more than one logical drive to migrate, you must add the disks one at a time to prevent confusion.
  4. On the Storwize V3700 system, complete the following steps to manage the logical unit.
    1. To create one empty storage pool, enter the following command.
      svctask mkmdiskgrp -ext extent_size
      The logical unit that was mapped from the DS3200/DS3500 system appears as an unmanaged-mode MDisk to the Storwize V3700.
    2. To list the unmanaged-mode MDisks, enter the following command.
      svcinfo lsmdisk
    3. If the new unmanaged-mode MDisk is not listed, perform a fabric-level discovery. Enter the following command to scan the network for the unmanaged-mode MDisks.
      svctask detectmdisk
    4. To convert the unmanaged-mode MDisk to an image mode volume disk, enter the following command.
      svctask mkvdisk -vtype image -iogrp iogrp_name -mdiskgrp -mdisk mdiskgrp_name 
       mdisk_name -mirrorwritepriority redundancy
      iogrp_name
      Name or ID of the I/O group.
      mdiskgrp_name
      Name or ID of the storage pool that you created in step 7.a.
      mdisk_name
      Name or ID of the unmanaged-mode MDisk.
    5. To get the SAS WWPN of hosts that were previously using the data that the MDisk now contains, enter the following command.
      svcinfo lssasportcandidate
    6. To create SAS hosts, enter the following command, where sas_wwpn is the SAS WWPN of the host server.
      svctask mkhost -saswwpn sas_wwpn
    7. Map the new volume to the SAS hosts. Enter the following command to create a new mapping between a volume and a host. The image mode volume becomes accessible for I/O operations to the host.
      svctask mkvdiskhostmap -host hostname diskname
      hostname
      Name or ID of the SAS host that was created in step 7.f.
      diskname
      Name or ID of the virtual disk created in step 7.d.
  5. On the host server, you can detect the new volume that is presented from the Storwize V3700 system and start I/O operations towards it.
  6. If you have more than one logical drive to migrate, repeat steps 6 through 8.
  7. On the Storwize V3700 system, complete the following steps to start migration for each image-mode volume.
    1. To create one empty internal storage pool, enter the following command.
      svctask mkmdiskgrp -ext  extent_size
    2. To create arrays with internal drives and add them to the internal storage pool, enter the following command.
      svctask mkarray -level raidtype -drive drivelist mdiskgrpname
      raidtype
      Type of RAID array to be created.
      drivelist
      List of drive IDs.
      mdiskgrpname
      Name or ID of storage pool created in step 10.a.
    3. After you determine the volume that you want to migrate and the new storage pool that you want to migrate it to, enter the following command.
      svctask addvdiskcopy -mdiskgrp newmdiskgrname vdiskname
      The copy ID of the new copy is returned. The copies now synchronize such that the data is stored in both storage pools.
    4. To check the progress of the synchronization, enter the following command.
      svcinfo lsvdisksyncprogress
    5. After the volume reports that it is fully synchronized and you are ready to stop using the external storage system, enter the following command on the image-mode copy of the volume.
      svctask rmvdiskcopy
      The image-mode copy is deleted, and its associated MDisk becomes unmanaged.

Results

The data on DS3200/DS3500 logical drives is migrated to the Storwize V3700 system. Host I/O is also switched to the Storwize V3700 system.

What to do next

You can now disconnect the SAS cabling between the DS3200/DS3500 system and the Storwize V3700 system.