Restoring SnapVault data to the primary storage system

About SnapVault data restoration

In the event of data loss on a primary storage system, restoring data from the SnapVault secondary storage system involves these command-line operations:

You use the snapvault restore command to restore a backed-up qtree from its last update saved to the secondary storage system.
After successfully restoring data, you use the snapvault start command to restart the SnapVault backup relationship between the primary and secondary qtrees (because you want to continue SnapVault protection of the data). If you do not want to continue the backup relationship, you use the snapvault release command to cancel any further backups of the restored qtree and to release the resources on the secondary storage system that were used in the SnapVault relationship.
Note
The descriptions and procedures in this section pertain to SnapVault backup of Data ONTAP storage systems only. For SnapVault backup of Open Systems drives and directories, see Setting up SnapVault backup on Open Systems platforms and Managing SnapVault backup of Open Systems platforms.

Restoring data to the primary storage system

To restore data from the SnapVault secondary storage system to the primary storage system, complete the following steps.

Step	Action
1	If you intend to restore a primary qtree to the exact qtree location on the primary storage system from which you backed it up, delete the existing qtree from the primary storage system.
2	Enter the following command on the primary storage system on a single line: snapvault restore [options] -S [sec_system:]sec_qtree_path [prim_system:]prim_qtree_path `-S` [sec_system:]sec_qtree_path specifies the secondary storage system and qtree path from which you want to restore the data. prim_system is the name of the primary storage system that you want to restore to. If specified, this name must match the name of the host system. prim_qtree_path is the name of the primary storage system qtree that you want to restore to. For options to the `snapvault restore` command, see the na_snapvault(1) man page.
3	If you want to...	Then...
	Resume SnapVault backups of the newly restored qtree on the primary storage system	Go to Step 4.
	Discontinue the backup relationship between the newly restored qtree on the primary storage system and its secondary qtree partner	Go to Step 6.
4	If you want to resume the SnapVault relationship between the restored qtree and its backup qtree on the secondary storage system, enter the following command on a single line: snapvault start -r [options] -S [prim_system:]prim_qtree_path [sec_system:]/vol/sec_volume/sec_qtree_path `-r` is required to restart backups from a restored primary storage system. See the na_snapvault(1) man page for details about the `snapvault` command syntax. Note To support data integrity in a restrictive SnapLock Compliance environment, the `snapvault start -r` operation saves all data that was written after the common Snapshot copy to a directory on the volume. For details see SnapVault resynchronization for SnapLock Compliance volumes.
5	You have finished. See Example 1.
6	If you want to discontinue the SnapVault relationship between the restored qtree and its backup qtree on the secondary storage system, enter the following command on the secondary storage system: snapvault release sec_qtree_path [prim_system:]prim_qtree_path sec_qtree_path is the name of the secondary storage system qtree that you want to release from a SnapVault relationship. [prim_system:]prim_qtree_path is the name of the primary storage system qtree that you want to release.
7	You have finished. See Example 2.

Example 1

This example shows the primary storage system (systemA) requesting data to be restored from the secondary storage system (systemB) and then the secondary storage system restarting the SnapVault backup relationship.

systemA> snapvault restore -S systemB:/vol/sv_vol/qtree3 
vol/vol1/qtree3

systemB> snapvault start -r -S systemA:/vol/vol1/qtree3 
systemB:/vol/sv_vol/qtree3

Example 2

This example shows the primary storage system (systemA) requesting data to be restored from the secondary storage system (systemB) and then the secondary storage system canceling the SnapVault backup relationship on both storage systems to release the resources used.

systemA> snapvault restore -S systemB:/vol/sv_vol/qtree3 
/vol/vol1/qtree3

systemB> snapvault release /vol/sv_vol/qtree3 
systemA:/vol/vol1/qtree3

Deleting the residual Snapshot copy

When you use the snapvault restore command to restore a primary qtree, SnapVault places a residual SnapVault Snapshot copy on the volume of the restored primary qtree. This Snapshot copy is not automatically deleted. If you have configured this volume to retain the maximum 251 Snapshot copies allowed by Data ONTAP, you must manually delete this residual Snapshot copy, or else no new Snapshot copies can be created.

To find and delete this residual Snapshot copy, complete the following steps.

Step	Action
1	To display all Snapshot copies (including the residual Snapshot copy) on the volume of the restored qtree, enter the following command: snap list primaryvolume The residual Snapshot copy will be distinguished by the following syntax: primaryhost (nvram_id)_primaryvolume_restoredqtree-dst.2 Example `prim_system (1880911275)_vol1_mytree-dst.2`
2	To delete the residual Snapshot copy, enter the following command: snap delete primaryvolume extrasnapshotname Example snap delete vol1 prim_system (1880911275)_vol1_mytree- dst.2

Step

Action

To display all Snapshot copies (including the residual Snapshot copy) on the volume of the restored qtree, enter the following command:

snap list primaryvolume

The residual Snapshot copy will be distinguished by the following syntax:

primaryhost (nvram_id)_primaryvolume_restoredqtree-dst.2

Example

prim_system (1880911275)_vol1_mytree-dst.2

To delete the residual Snapshot copy, enter the following command:

snap delete primaryvolume extrasnapshotname

Example

snap delete vol1 prim_system (1880911275)_vol1_mytree-
dst.2