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1
Q

What is SnapVault?

A

SnapVault is a disk-based storage backup feature of Data ONTAP. SnapVault enables data stored on multiple systems to be backed up to a central, secondary system quickly and efficiently as read-only Snapshot copies.

In the event of data loss or corruption on a system, backed-up data can be restored from the SnapVault secondary system with less downtime and uncertainty than is associated with conventional tape backup and restore operations.

The following terms are used to describe the SnapVault feature:

Primary system—a system whose data is to be backed up
Secondary system—a system to which data is backed up
Primary system qtree—a qtree on a primary system whose data is backed up to a secondary qtree on a secondary system
Secondary system qtree—a qtree on a secondary system to which data from a primary qtree on a primary system is backed up
Open systems platform—a server running AIX, Solaris, HP-UX, Red Hat Linux, SUSE Linux, or Windows, whose data can be backed up to a SnapVault secondary system
Open Systems SnapVault agent—a software agent that enables the system to back up its data to a SnapVault secondary system
SnapVault relationship—the backup relationship between a qtree on a primary system or a directory on an open systems primary platform and its corresponding secondary system qtree
SnapVault Snapshot copy—the backup images that SnapVault creates at intervals on its primary and secondary systems
SnapVault Snapshot copies capture the state of primary qtree data on each primary system. This data is transferred to secondary qtrees on the SnapVault secondary system. The secondary system creates and maintains versions of Snapshot copies of the combined data for long-term storage and possible restore operations.
SnapVault Snapshot basename—a name that you assign to a set of SnapVault Snapshot copies using the snapvault snap sched command. As incremental Snapshot copies for a set are taken and stored on both the primary and secondary systems, the system appends a number (0, 1, 2, 3, and so on) to the basenames to track the most recent and earlier Snapshot updates.
SnapVault baseline transfer—an initial complete backup of a primary storage qtree or an open systems platform directory to a corresponding qtree on the secondary system
SnapVault incremental transfer—a follow-up backup to the secondary system that contains only the changes to the primary storage data between the current and last transfer actions

2
Q

How do you Plan SnapVault backups?

A

Before starting SnapVault backups, you need to plan your primary system qtrees or open systems directories and their corresponding secondary system qtrees. You also need to plan the SnapVault backup schedule and Snapshot copy retention, and estimate the initial backup time.

3
Q

How do you enable SnapVault?

A

Setting up SnapVault backup on the primary systems means preparing the primary storage system and SnapVault secondary storage system to perform their backup tasks. In Data ONTAP 8.2 and later, a single SnapVault license is used for SnapVault primary and SnapVault secondary instead of two separate SnapVault licenses. You must license and prepare your storage system before you can use SnapVault to back up data.

4
Q

How do you start a SnapVault backup relationship?

A

After you have enabled SnapVault on both the primary and secondary storage systems and have provided the primary and secondary storage systems access to each other, you must specify the qtrees or volumes whose data you want transferred from the primary storage system to the SnapVault secondary storage system. You must then perform a complete (baseline) transfer of data from the primary storage system to secondary storage system.

The snapvault start command configures the SnapVault relationship between primary qtrees or volumes and secondary qtrees by specifying the following:
The primary storage system qtrees or volumes to be backed up on the storage system qtrees
The parameters for the updates from the primary storage system qtrees to the secondary storage system qtrees
These parameters include transfer speed and try count. Try count is the number of times SnapVault attempts to start a transfer before stopping the operation.
The snapvault start command also initiates the baseline transfer of the primary storage system qtree data to the secondary storage system qtree

5
Q

What are SnapVault Snapshot copy update schedules?

A

After you have completed the initial baseline backup of qtrees on the primary system to qtrees on the SnapVault secondary system, you must use the snapvault snap sched command to schedule a set of Snapshot copies on the SnapVault primary system. You can also specify the volume to create Snapshot copies for, the Snapshot copy basename, how many versions of the Snapshot copies to retain, and the days and hours to create this set of Snapshot copies.

You must use the snapvault snap sched command to schedule the following tasks:
Regular SnapVault Snapshot copy times of volumes on the primary system to capture new and changed data in the qtrees that have a SnapVault relationship configured through the snapvault start command
Regular transport of new or modified data in the primary qtrees to their associated secondary qtrees on the SnapVault secondary system
Regular Snapshot copies of the volume containing the updated secondary qtrees for archiving by SnapVault

6
Q

How do you Unschedule SnapVault Snapshot copies?

A

You can unschedule a set of SnapVault Snapshot copies if the data in the qtrees you are backing up has been migrated to another location or is no longer useful.

Step
To turn off the SnapVault schedule for a set of Snapshot copies and stop the Snapshot copy process for the SnapVault primary system or secondary system, enter the following command at the console of the primary or secondary system:
snapvault snap unsched [-f] [volume [snap_name]]
-f forces the command to run without showing the list of Snapshot copies to stop creating and without asking for confirmation.
volume is the name of the volume to stop creating Snapshot copies on.
snap_name is the basename of the Snapshot copy set to stop creating.
If no value for snap_name is provided, SnapVault turns off the SnapVault Snapshot copy schedule for all Snapshot copy sets in the volume and does not update any more SnapVault Snapshot copies in the volume. If no volume is provided, SnapVault deletes the schedules for all SnapVault Snapshot copy sets and does not update any more SnapVault Snapshot copies in the system. If there is already a Snapshot copy being created in the volume, the command fails.

Example
systemB> snapvault snap unsched vol1 sv_nightly
Unless you used the -f option, SnapVault asks for confirmation. If you confirm the action, SnapVault unschedules all SnapVault Snapshot copies with the basename sv_nightly on vol1 of systemB.

7
Q

How to check SnapVault Transfers?

A

To ensure SnapVault transfers are taking place as expected, you can check the transfer status using the snapvault status command.

Step
To check the status of a data transfer and see how recently a qtree has been updated, enter the following command:
snapvault status [-l|-s|-c|-t] [[[system_name:]qtree_path] …]
-l displays the long format of the output, which contains more detailed information.
-s displays the SnapVault Snapshot copy basename, status, and schedule for each volume.
-c displays the configuration parameters of all SnapVault qtrees on the system. This option can be run only from the secondary system.
-t displays the relationships that are active.
Note: A relationship is considered active if the source or destination is involved in any one of the following activities: transferring data to or from the network, reading or writing to a tape device, waiting for a tape change, or performing local on-disk processing or clean-up.
system_name is the name of the system for which you want to see the status of SnapVault operations.
qtree_path is the path of the qtree or qtrees for which you want to see the status of SnapVault operations. You can specify more than one qtree path.
The system displays a message showing whether a transfer is in progress, how much data has been transferred, the state of the destination, and how long ago the last successful transfer took place.
If [system_name:]qtree_path arguments are specified, then status is displayed only for the specified qtrees.
If the -l option is given, the output includes the more detailed information shown in Example 2.
If the -s option is given, the output displays Snapshot copy creation status, as shown in Example 3.
If the -c option is given, the output displays the parameter settings for the primary system configuration, as shown in Example 4.
If the -t option is given, the output displays the list of relationships that have active transfers as shown in Example 5.
Data ONTAP allows you to set a maximum rate for transfers coming into a system and for transfers going out of a system.

8
Q

How do you Display SnapVault Snapshot copies?

A

You can use the snap list command to display a list of Snapshot copies to confirm what versions of your primary qtree data have been backed up, or to locate by date or time a particular version of a qtree to retrieve.

Using the snap list -q command, you can see the following:
A list of all Snapshot copies on the secondary storage system (not just SnapVault Snapshot copies)
The qtrees in the Snapshot copies
The primary storage system sources of those qtrees
The timestamp of the primary storage system Snapshot copy that was the source for the data in the secondary storage system Snapshot copy
Using the snap list -o command, you can also list the Snapshot copy timestamps, primary qtree origin (if applicable), and Snapshot copy names stored for an individual qtree.
Note: The descriptions and procedures pertain to SnapVault backup of storage systems running Data ONTAP only. For descriptions and procedures pertaining to SnapVault backup of open systems drives and directories, see the Open Systems SnapVault documentation.
More information
Displaying SnapVault Snapshot copies on a volume
You can display a list of the Snapshot copies and qtrees on your volumes, by using the snap list command.
Listing Snapshot copies for qtrees
You can use the snap list command to see a list of Snapshot copies associated with a qtree and, if applicable, the Snapshot copies’ primary qtree origins.

9
Q

What are LUN clones in SnapVault

A

A LUN clone is a space-efficient copy of another LUN. Initially, the LUN clone and its parent share the same storage space. More storage space is consumed only when one LUN or the other changes.

In releases prior to Data ONTAP 7.3, SnapVault considers each LUN clone as a new LUN. Therefore, during the initial transfer of the LUN clone, all data from the clone and the backing LUN is transferred to the secondary system.

Note: LUNs in this context refer to the LUNs that Data ONTAP serves to clients, not to the array LUNs used for storage on a storage array.
For descriptions of data backup and restore on volumes containing LUNs, see the Data ONTAP SAN Administration Guide for 7-Mode.

Starting with Data ONTAP 7.3, SnapVault can transfer LUN clones in an optimized way by using SnapDrive for Windows. To manage this process, SnapDrive for Windows creates two Snapshot copies:
Backing Snapshot copy, which contains the LUN to be cloned
Backup Snapshot copy, which contains both the LUN and the clone
Modes of transfer

Starting with Data ONTAP 7.3, a SnapVault transfer with LUN clones can run in two modes:
In non-optimized mode, a LUN clone is replicated as a LUN. Therefore, a LUN clone and its backing LUN get replicated as two separate LUNs on the destination. SnapVault does not preserve space savings that come from LUN clones.
In optimized mode, a LUN clone is replicated as a LUN clone on the destination. Transfers of LUN clones to the secondary system in optimized mode are possible only with SnapDrive for Windows.
These modes apply to newly created LUN clones. On successive update transfers, only the incremental changes are transferred to the destination in both modes.
Note: A single relationship must either be optimized or non-optimized. Switching between the two modes is not allowed.

10
Q

How to you change SnapVault settings?

A

You can use the snapvault modify command to change the primary system (source) qtree that you specified using the snapvault start command. You can change the SnapVault settings for transfer speed and number of tries before quitting. You might need to make these changes if there are hardware or software changes to the systems.

The meaning of the options is the same as for the snapvault start command. If an option is set, it changes the configuration for that option. If an option is not set, the configuration of that option is unchanged.

Note: The descriptions and procedures in this section pertain to SnapVault backup of systems running Data ONTAP only. For descriptions and procedures pertaining to SnapVault backup of open systems drives and directories, see the Open Systems SnapVault documentation.
The snapvault modify command is available only from the secondary system. You can also use this command to modify the tries count after the relationship has been set up. This is useful when there is a planned network outage.

You use the snapvault modify command to change the source if the primary system, volume, or qtree is renamed. This ensures the continuity of the existing SnapVault relationship between the primary and secondary systems. However, you cannot copy a primary qtree to another volume or system and use this command to take backups from that new location.

If you need to change the SnapVault schedule, use the snapvault snap sched command.

11
Q

Why do you manually update a qtree on the secondary system?

A

You can use the snapvault update command to manually update the SnapVault qtree on the secondary system from a Snapshot copy on the primary system. You might want to update at an unscheduled time to protect the primary system data.

Manual updates are useful in the following situations:
A disk failed on the primary system and you want extra protection for the data.
The nightly backup failed due to a network problem.
The primary system hardware is going to be reconfigured.
You want to transfer a Snapshot copy of a quiesced database.
Note: The descriptions and procedures in this section pertain to SnapVault backup of systems running Data ONTAP only. For SnapVault backup of open systems drives and directories, see the Open Systems SnapVault documentation.

12
Q

Why would you create a Snapshot copy manually?

A

In certain cases, you might want to create a manual (unscheduled) Snapshot copy.

Creating a manual Snapshot copy is useful in these situations:
You anticipate planned downtime or you need to recover from downtime (during which a Snapshot copy was not taken on time).
You have just carried out a manual update of a secondary qtree, and you want to immediately incorporate that update into the retained Snapshot copies on the secondary system.
Note: The descriptions and procedures pertain to SnapVault backup of systems running Data ONTAP only. For descriptions and procedures pertaining to SnapVault backup of open systems drives and directories, see the Open Systems SnapVault documentation.

13
Q

What do you need to do if you Rename a SnapVault or Open Systems SnapVault secondary volume?

A

If you rename a volume involved in a SnapVault relationship, you need to update the SnapVault configurations with the new name.

About this task
If the qtree is not configured in SnapVault, using the snapvault start command to configure the qtree gives the following error:
Error: Not a snapvaulted qtree, ignoring.
This error means that the qtree is not a SnapVault replica.
Steps
To rename a volume, enter the following command:
vol rename oldvolname newvolname
To verify the changes, enter the following command:
snapvault status -c
snapvault status -c does not show the new path yet.
Enter the following command:
snapvault start -S pri_filer:pri_qtree sec_filer:sec_qtree
Snapvault configuration for the qtree has been set. Qtree /vol/newvolname/sec_qtree is already a replica.
Enter the following command:
snapvault status -c
snapvault status -c now shows the new path.
Enter the following command to verify that the change was successful:
snapvault update sec_qtree
The output of snapvault status -c will contain entries referencing the old volume name in addition to the new volume name. Remove the old entries by using the snapvault stop command:
snapvault stop /vol/oldvolname/sec_qtree
Snapvault configuration for the qtree has been deleted. Could not delete qtree: destination qtree does not exist
The output reflects that the configuration information is deleted and that the qtree did not exist on disk. This is normal because the volume name has changed.

14
Q

Restoring SnapVault data to the primary system

A

In the event of data loss on a primary system, you might need to restore data from the secondary system.

About this task
Restoring data from the SnapVault secondary system involves the following command-line operations.
You use the snapvault restore command to restore a backed-up qtree saved to the secondary system. Starting with Data ONTAP 7.3, you can restore the data to an existing qtree on the primary system using baseline restore or incremental restore.
Baseline restore: The primary system must be running Data ONTAP 7.3 or later, and the secondary system can be running any Data ONTAP version.
Incremental restore: Both the primary and secondary systems must be running Data ONTAP 7.3 or later.
Note: Starting with Data ONTAP 7.3, the SCSI connectivity of applications to all LUNs within the qtree being restored is maintained throughout the restore process in order to make the restore operation nondisruptive to applications. However, I/O operations are not allowed during the restore operation. Only in-place baseline restores and incremental restores can be nondisruptive.
After successfully restoring data, you use the snapvault start -r command to resume the SnapVault relationship between the restored qtree and its backup qtree on the secondary system (assuming 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 system that were used in the SnapVault relationship.
When several SnapVault restore operations to different primary qtrees in the same volume are running concurrently, Snapshot cleanup might fail due to Snapshot copies being locked by various restore operations. Therefore, some unwanted Snapshot copies might be left behind in the volume.
You can manually delete these unwanted Snapshot copies. Make sure that you do not delete the base Snapshot copy of the restore operation.
Note: If you do not want to resume the relationship, you can delete the Snapshot copy created by the restore operation. If you want to resume the SnapVault operation, you can delete the Snapshot copy after you have successfully resumed the relationship.

15
Q

How do you abort SnapVault transfers?

A

You can use the snapvault abort command to halt an ongoing SnapVault transfer if a later transfer is more useful or if an immediate shutdown or restart is necessary.

This command can halt ongoing SnapVault transfers from primary to secondary storage system (invoked by the snapvault start or snapvault update commands or scheduled through the snapvault snap sched -x command), or from secondary back to primary storage system (invoked by the snapvault restore command).

You can enter the snapvault abort command at the primary storage system or at the secondary storage system.

16
Q

How do you end SnapVault backups for a qtree?

A

You can use the snapvault stop command to end the SnapVault backup process for a qtree when you no longer need the data in the primary system qtree to be protected.

About this task
After you use the snapvault stop command, SnapVault stops updating the qtree on the secondary system and deletes the qtree. Existing Snapshot copies on the secondary system are unaffected, but as new Snapshot copies replace the old ones, the data from the qtree whose backup was stopped disappears.
Step
From the secondary system, enter the following command:
snapvault stop [sec_system:]sec_qtree_path
[sec_system:]sec_qtree_path is the qtree that you no longer want to back up.
Example
systemB> snapvault stop systemB:/vol/sv_vol/qtree3
Note: After you end the backup process from a SnapVault secondary system, you might want to release the obsolete Snapshot copies on the primary system.

17
Q

How do you Release SnapVault relationships

A

There are two methods of releasing a SnapVault relationship between a primary qtree and its secondary qtree backup (originally defined through the snapvault start command) after the relationship is no longer needed.

About this task
You can release SnapVault relationships in the following scenarios:
On a primary storage system, as a part of shutting down a SnapVault relationship after a snapvault stop command was completed on the secondary storage system.
On the secondary storage system, after data is restored to a primary storage system and you do not want to reactivate the backup relationship between the primary and secondary qtrees.
Steps
On a primary storage system console, enter the following command:
snapvault release prim_qtree_path sec_system:sec_qtree_path
On the secondary storage system console, enter the following command:
snapvault release sec_qtree_path prim_system:prim_qtree_path
Example
systemB> snapvault release /vol/sv_vol/qtree3 systemA:/vol/vol1/qtree3

18
Q

How do you turn SnapVault off?

A

You can turn SnapVault off by using the snapvault.enable option if the files on the primary or secondary storage system are no longer important or current or have been moved to another location.

Step
To turn off SnapVault on a primary storage system or secondary storage system, enter the following command:
options snapvault.enable off
This option persists across reboots.

19
Q

What is the Compression feature of Open Systems SnapVault?

A

The compression feature of Open Systems SnapVault enables data compression over the network. This feature helps optimize bandwidth usage for Open Systems SnapVault data transfers.

Data ONTAP 7.3 and later support bandwidth optimization for Open Systems SnapVault through the compression feature. However, SnapVault primary systems do not support bandwidth optimization.

When you want to compress the network data, you can use global or local compression options.

20
Q

What is SnapVault secondary system protection?

A

By setting up a SnapMirror relationship between the SnapVault secondary storage system and a SnapMirror destination storage system, NearStore system, or tape backup unit, you can provide backup and standby service or backup and restore protection for the SnapVault secondary storage system data.

SnapMirror backup and standby service for SnapVault uses the SnapMirror destination device as a standby device to be activated as an alternate SnapVault secondary storage system if the original secondary storage system goes down.
SnapMirror backup and restore protection for SnapVault uses the SnapMirror destination device as a source from which you can restore backup data to a SnapVault secondary storage system that has suffered data loss or corruption.

21
Q

How you you use SnapVault to protect a volume SnapMirror destination?

A

You can use SnapVault to protect a volume SnapMirror destination. You can perform SnapVault transfers from the volume SnapMirror destination when you want to retain the data for a longer period.

In this deployment scenario, data from various primary systems is replicated to a remote site for disaster recovery. Volume SnapMirror ensures identical data at the source and destination systems. If you want to retain the data for a longer duration (that is, 90 days and more) at the disaster recovery site, you can use SnapVault to back up data from the SnapMirror destination.

When using SnapVault to back up a SnapMirror destination volume or qtree, you need to ensure the following:
The SnapMirror license is installed on the SnapMirror primary system and the SnapMirror secondary system (which also acts as the SnapVault primary system). The SnapVault license is installed on the SnapVault primary system (which also acts as the SnapMirror secondary system) and the SnapVault secondary system.
The SnapVault operation occurs between SnapMirror scheduled updates. SnapMirror updates fail if a SnapVault operation is initiated or in progress.
Before performing a SnapVault transfer for a particular Snapshot copy, this Snapshot copy must be preserved on the primary system.
To use the SnapVault backup schedule, you need to configure the SnapVault primary schedule at the volume SnapMirror primary system. Therefore, you need the SnapVault license installed on the volume SnapMirror primary system. However, you do not need the SnapVault license on the volume SnapMirror primary system if you want to use the Snapshot copies created by SnapMirror.

For more information about disaster recovery and long-term backup of data, see the technical report SnapMirror Async Overview and Best Practices Guide.

22
Q

SnapVault behavior when used for volume SnapMirror destination protection

A

When SnapVault is used to protect the volume SnapMirror destination, SnapVault uses the Snapshot copy based on the Data ONTAP version that is running on the SnapMirror destination system, when SnapVault schedule is used within Data ONTAP.

SnapVault behavior varies according to the Data ONTAP version running on the SnapMirror destination system.

Data ONTAP 7.3.2 and earlier: SnapVault ignores any specified (named) Snapshot copy and uses the most recent volume SnapMirror Snapshot copy for backup.

Data ONTAP 7.3.2 to 7.3.4 and Data ONTAP 8.0 7-Mode: SnapVault updates only from a specific named Snapshot copy and it does not use the Snapshot copy created by volume SnapMirror.

Data ONTAP 7.3.5 and later: You can choose the SnapVault behavior for updating the destination system. SnapVault can use either the Snapshot copy created by volume SnapMirror or a named Snapshot copy.