Restore a single LUN from a SnapVault backup

Contributors

You can restore a single LUN to a new location or to the original location. You can restore from any Snapshot copy in the SnapVault secondary volume. To restore the LUN to the original location, you first restore it to a new location and then copy it.

What you’ll need
  • The SnapVault relationship must be initialized and the SnapVault secondary volume must contain an appropriate Snapshot copy to restore.

  • The storage virtual machine (SVM) containing the SnapVault secondary volume must have one or more LIFs with the desired SAN protocol that are accessible from the host used to access the LUN copy.

  • The igroups must already exist on the SnapVault SVM.

About this task

The process includes creating a read-write volume clone from a Snapshot copy in the SnapVault secondary volume. You can use the LUN directly from the clone, or you can optionally copy the LUN contents back to the original LUN location.

The LUN in the clone has a different path and serial number from the original LUN. Persistent reservations are not retained.

Steps
  1. Run the snapmirror show command to verify the secondary volume that contains the SnapVault backup.

    cluster::> snapmirror show
    
    Source         Dest     Mirror  Relation  Total             Last
    Path     Type  Path     State   Status    Progress  Healthy Updated
    -------- ---- --------- ------- --------- --------- ------- -------
    vserverA:srcvolA
             XDP  vserverB:dstvolB
                            Snapmirrored
                                    Idle       -         true    -
  2. Run the volume snapshot show command to identify the Snapshot copy that you want to restore the LUN from.

    cluster::> volume snapshot show
    
    Vserver  Volume  Snapshot               State Size   Total% Used%
    -------- ------- ---------------------- ----- ------ ------ -----
    vserverB
             dstvolB
                     snap2.2013-02-10_0010  valid  124KB     0%    0%
                     snap1.2013-02-10_0015 valid  112KB     0%    0%
                     snap2.2013-02-11_0010  valid  164KB     0%    0%
  3. Run the volume clone create command to create a read-write clone from the desired Snapshot copy.

    The volume clone is created in the same aggregate as the SnapVault backup. There must be enough space in the aggregate to store the clone.

    cluster::> volume clone create -vserver vserverB
      -flexclone dstvolB_clone -type RW -parent-volume dstvolB
      -parent-snapshot daily.2013-02-10_0010
    [Job 108] Job succeeded: Successful
  4. Run the lun show command to list the LUNs in the volume clone.

    cluster::> lun show -vserver vserverB -volume dstvolB_clone
    
    Vserver   Path                      State   Mapped   Type
    --------- ------------------------  ------- -------- --------
    vserverB  /vol/dstvolB_clone/lun_A  online  unmapped windows
    vserverB  /vol/dstvolB_clone/lun_B  online  unmapped windows
    vserverB  /vol/dstvolB_clone/lun_C  online  unmapped windows
    
    3 entries were displayed.
  5. If the igroup for the desired host does not already exist on the SVM containing the SnapVault backup, run the igroup create command to create an igroup.

    This example creates an igroup for a Windows host that uses the iSCSI protocol:

    cluster::> igroup create -vserver vserverB -igroup temp_igroup
      -protocol iscsi -ostype windows
      -initiator iqn.1991-05.com.microsoft:hostA
  6. Run the lun mapping create command to map the desired LUN copy to the igroup.

    cluster::> lun mapping create -vserver vserverB
      -path /vol/dstvolB_clone/lun_C -igroup temp_igroup
  7. Connect the host to the LUN and access the contents of the LUN, as desired.

    The LUN is read-write and can be used in place of the original LUN. Because the LUN serial number is different, the host interprets it as a different LUN from the original.

  8. Use a copy program on the host to copy the LUN contents back to the original LUN.