How to mount a block snapshot or replication as an RDM disk on a VM

Ops Center Protector VMware Application Guide

Part Number

It is assumed that a policy that creates hardware snapshot/replications has been implemented and that at least one snapshot/replication has been created on the designated Hitachi Block Storage device.

Note: The mount target VM must:
  • Have VMware Tools installed.
  • For Host and OS level mounting - have Protector Client software installed and appear as an online OS Host node in the Nodes Inventory. For SAN level mounting, Protector Client software does not need to be installed.
    Tip: SAN level mounting enables operations to be performed that differ from the Protector mount process.
  • For the auto-discover host group feature to work on the Block Snapshot or Replication Mount Wizard - have a pre-existing LUN mounted from the corresponding Block storage device. If not then the host group must be manually selected.

This task describes the steps to follow when mounting a snapshot/replication of a physical LDEV from a Block storage device, as an RDM on a VM:

  1. Identify the VMware Server where the mount target VM is hosted. The destination host must be represented by an Protector VMware node. If necessary, create one using the VMware Node Wizard.
    The VMware node type is grouped under Hypervisor in the Node Type Wizard. There is no need to create a new VMware host if the required one already exists.
  2. Ensure that the target VM is prepared to receive the snapshot/replication by locating it on the VMware Server and ensuring it is powered on.
  3. Locate the snapshot/replication to be mounted by navigating to the Block Snapshots/Replications Inventory for the block storage device in question.
  4. Select the snapshot/replication to be mounted, then click Mount to open the Block Snapshot or Replication Mount Wizard.
    1. Select SAN, Host or OS mount level:
    2. Choose a Host Group or allow Protector to Automatically discover a suitable one for the VMware Server hosting the target VM.
    3. For SAN level mount, click Finish. For all other mount levels click Next.
    4. Specify the OS Host (i.e. the target VM where the RDM disk will be mounted). The Protector Client must be installed on this VM for it to appear in the list.
    5. Specify the VMware Node (i.e. the VMware Server where the target VM is hosted).
    6. Optionally specify a Datastore if the default is not desired or suitable.
    7. For Host level mount click Finish. For OS level mount click Next.
    8. For OS level mount, specify the Mount Location as a Drive starting at letter or a Directory. The specified mount location must not be in use otherwise the mount operation will fail.
    9. If mounting a snapshot, select the mount mode and specify the Mount Pool if necessary, then click Finish.
      The Mount duplicate option is disabled for replications and non-cascade mode snapshots.
      Select the mount mode depending on the behaviour required:
      • Mount original - Any changes made to the mounted RDM disk will persist after the original snapshot/replication is unmounted.
      • Mount duplicate - Any changes made to the mounted RDM disk for a duplicate snapshot will be lost when the snapshot is unmounted. If you want to preserve the original snapshot, use Cascade mode (the default setting) in the Block Snapshot Configuration Wizard when assigning the snapshot operation on the data flow. This will enable the Mount duplicate option when mounting.
    The Jobs Inventory is displayed and a mount job will appear that cycles through stages and ending in Progress - Completed.
    Tip: In the event of an error you will see the following log message in the Logs Inventory:

    VMware host mount operation failed *** Attachment count 1 ***

    Click the Session icon to the left of this message to display the Session Log. All log messages generated during the mount sequence are displayed to help diagnose the problem.

  5. Once the mount process is complete, further steps may be needed to fix-up the data set before using it.
    The amount of fix-up work required depends on the applications accessing the restored data.
  6. Once the mounted RDM disk is finished with, click Unmount on the corresponding tile in the Block Snapshots/Replications Inventory to unmount it.
    Mounted snapshots/replications have a mount icon displayed next to them.