Remounting DMMP devices on Linux hosts after transition

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After transition from ONTAP operating in 7-Mode to clustered Data ONTAP, you must remount your DMMP devices for RHEL 5 and RHEL 6. Your 7-Mode LUNs are not accessible to the host until your DMMP devices are mounted.

If you are doing a copy-free transition (CFT), procedures for vol rehost must be complete. See the 7-Mode Transition Tool Copy-Free Transition Guide for details.

  • For copy-based transitions, perform these steps after completing the Storage cutover operation in the 7-Mode Transition Tool (7MTT).

  • For CFTs perform these steps after the Import Data & Configuration operation in the 7MTT is complete.

Steps
  1. Generate the 7-Mode to ONTAP LUN mapping file:

    • For copy-based transitions, run the following command from the Linux host where the 7MTT is installed:
      transition cbt export lunmap -p project-name -o file_path

      For example:

      transition cbt export lunmap -p SanWorkLoad -o c:/Libraires/Documents/7-to-C-LUN-MAPPING.csv

    • For copy-free transitions, run the following command from the system where the 7MTT is installed:
      transition cft export lunmap -p project-name -s svm-name -o output-file

      For example:

      transition cft export lunmap -p SanWorkLoad -s svml -0 c:/Libraries/Documents/7-to-C-LUN-MAPPING-svml.csv

      You must run this command for each of your storage virtual machines (SVMs).
  2. Make a note of the new ONTAP LUN device handle ID from the LUN mapping file.

  3. Remove the SCSI devices created for 7-Mode LUNs:

    • To remove all of the SCSI devices:
      rescan-scsi-bus.sh -r

    • To remove each SCSI device individually:
      echo 1> /sys/block/SCSI_ID/delete

      This command must be executed on all 7-Mode LUN SCSI devices. See the SCSI Device ID column on the SAN Host LUNs tab of the Inventory Assessment Workbook to identify the SCSI device IDs for the LUNs.

  4. Discover new ONTAP LUNs:

    rescan-scsi-bus.sh

  5. Verify that the ONTAP LUNs are discovered:

    sanlun lun show

    The ONTAP LUN’s SCSI devices should be listed under the filename column.

  6. Configure DMMP devices for ONTAP LUNs:

    multipath

  7. Verify that the DMMP devices are present:

    multipath -ll LUN_SCSI_device_name

    In the following example, 3600a098051764937303f4479515a7451 represents the DMMP device handle ID:

    [root@IBMx3550M3-229-169 ~]#multipath -ll /dev/sdq
    3600a098051764937303f4479515a7451 dm-6 NETAPP,LUN C-Mode
  8. Mount the LUN:

    *mount device_name mountpoint

    If the mount points are defined in the /etc/fstab file, you can run the mount -a command to mount all of the mount points.

  9. Verify the mount points:

    mount