The snapshots of the data created by the SnapProtect backup are also
available for various other operations like list, mount, unmount, delete, or
revert.
The browse operation provides the capability to see the snapshots created for
an agent, job, or a snapshot copy. The list of the snapshots displayed is corresponding
to the entity selected for the browse operation, for e.g., browsing the snapshots
for an agent will display all the snapshots created for the selected agent. You can
view volume or disk related information for the snapshots. Follow the steps given
below to browse snapshots.
From the CommCell Browser, navigate to Client Computers | <Client>
| <Agent>.
Right-click the subclient and click List Snaps.
The Snaps created during SnapProtect operation dialog box displays a list of
all the snapshots created for the selected subclient. It also displays important
information about each snapshot, including the source month path, snap mount
path, the storage array, and the source client.
Click the Disk View
tab to display the snapshot name, e.g.
SP_2_79_1286222629.
You can also browse snapshots at the instance level of the DB2 Agent.
You can mount any available snapshot to access the data included in the
snapshot. It is recommended that you select the option to protect a snapshot
when it is mounted, as this will ensure that the changes made to the snapshot
when it is mounted are not retained when you unmount the snapshot and the
snapshot is usable for data protection operations. Follow the steps given below
to mount snapshots:
From the CommCell Browser, navigate to Client Computers | <Client>
| <Agent>.
Right-click the subclient and click List Snaps.
Right-click the snapshot that you wish to mount and click Mount.
Click Yes.
In the Mount Path dialog box, specify the destination client and the path on the client in the
Destination Client and Destination Path fields.
On a Windows
platform, enter a CIFS Share Name for the Agent.
If you do not wish to save
any changes made to the mounted snapshot after the snapshot is unmounted,
select Protect Snapshot during mount.
Click OK.
If you do not select Protect Snapshot
during mount,the changes made to snapshot when it is mounted will be retained
after the snapshot is unmounted and the snapshot can no longer be
used for restore.
Unmount Snapshots
Follow the steps given below to unmount snapshots:
From the CommCell Browser, navigate to Client Computers | <Client>
| <Agent>.
Right-click the subclient and click List Snaps.
Right-click the snapshot you
wish to unmount and click Unmount.
Click Yes when prompted if you want to continue.
If the snapshot does not get unmounted,
select the Force Unmount option to mark the snapshot as
unmounted.
Snapshots can either be deleted using job-based pruning or from the list of
displayed snapshots when browsing snapshots. Data Aging can also be used to
define the retention rules and pruning of snapshots. Follow the steps given
below to delete snapshots:
Manual deletion of snapshots is not recommended. When a
snapshot is deleted, it is no longer possible to perform data
recovery operations from the snapshot copy. However, if a backup
copy was created from the snapshot, data recovery operations can
be performed from the backup copy.
Ensure that the snapshot to be deleted is not mounted.
From the CommCell Browser, navigate to Client Computers | <Client>
| <Agent>.
Right-click the subclient and click List Snaps.
Right-click
the snapshot you wish to delete.
Ensure all snapshots with the same Job ID
are selected for a successful deletion operation.
Click Delete.
Enter the confirmation
text string, erase snapshots.
You can use the revert operation to bring the data back to the point-in-time
when the snapshot was taken. This operation overwrites any modifications to the data
since the time when the snapshot was created. This option is available if
the storage arrays that you are using supports revert.
Revert operations are supported on NetApp File Servers but
not from SnapVault or SnapMirror snapshots. You can either perform an
application aware revert or a hardware specific revert.
Review the following before performing a revert operation:
RevertSnapVolume has been set to 1.
Ensure that the archived redo log files and their mirror log files
reside on the same array volume.
After a revert or restore operation is completed successfully, you must also
run the ./brrestore –d util_file –b last –m 0 job to restore control files.
When using HP EVA Clone or Data Replicator for SnapProtect backup, the revert operation is not supported.
On Unix clusters, use pre/post scripts to freeze and unfreeze the
cluster for revert operations. For example, on Red Hat Linux cluster,
use the following command in the pre/post scripts:
clusvcadm -Z <group> to freeze the
cluster
clusvcadm -U <group> to unfreeze the
cluster
This is required because, during revert the application is shut down
and corresponding volumes are unmounted. In that case, the cluster will
automatically failover to another node thus preventing the revert
operation.
It is recommended to verify the
contents of the backup and ensure that you want to perform a revert operation
as it is an irreversible operation.
If you plan to perform a revert operation, you
will not be able to use the associated storage policy for further
auxiliary copy operations.
Perform an Application Aware Revert
From the CommCell Browser, right-click the entity
that contains the data you want to restore, and click All Tasks | Browse Backup Data.
From the Browse Options dialog box, click OK.
Select the data you want to revert and click Recover All Selected.
From the Restore Options dialog box, click Advanced.
Select the Use hardware revert
capability if available
option.
Click OK to confirm the revert operation.
Click OK from the Advanced Restore Options dialog box.
Click OK to start the revert.
An application aware revert operation reverts
back all the volumes included in the backup.
For NetApp NFS configurations:
This operation reverts all data on the file server volume, not just the
data that is associated with the application.
A volume revert deletes all snapshots that were created
after the snapshot to which you are reverting.
If you perform a volume revert on the source for a
SnapVault/SnapMirror copy, and the snapshot to which you are
reverting was created before the most recent snap moved to
the SnapVault/SnapMirror copy, then the SnapVault/SnapMirror
copy operation no longer works.
Perform a Hardware Specific Revert
From the CommCell Console, navigate to Client Computers |
<Client>.
Right-click the subclient and click List Snaps.
Right-click the snapshot that you wish to delete and click Use hardware revert
capability if available.
Enter the confirmation
text string, confirm.
Click OK.
A hardware specific revert operation reverts back
the volume included in the snapshot.
For NetApp NFS configurations:
This operation reverts all data on the file server volume, not just the
data that is associated with the snapshot.
A volume revert deletes all snapshots that were created
after the snapshot to which you are reverting.
If you perform a volume revert on the source for a SnapVault/SnapMirror
copy, and the snapshot to which you are reverting was created
before the most recent snap moved to the SnapVault/SnapMirror
copy, then the SnapVault/SnapMirror copy operation no longer
works.
Snapshots may be deleted from the array due to factors like low disk space on
the array, number of snapshots exceeds the threshold etc., and the jobs corresponding
to these deleted snapshots can no longer be used for any data recovery or backup
copy operations. You can use the
nRunSnapRecon
registry key to start snap reconciliation to check for missing snapshots once in
every 24 hours and marks jobs corresponding to the missing snapshots as invalid.
Use
sSKIPONLINELOGSNAP registry key
to exclude the
online logs during the snap backup if the log volumes are separated from data
volumes in DB2 database.
From the CommCell Browser, navigate to the Client Computers.
Right-click the <Client>, and then click Properties.
You can restore a database from a point in time. This is useful if you want to
restore certain configurations/contents in the database that are not reflected
in the latest backup. For example, you can use this option to restore a SnapProtect backup
if your latest backup was a traditional backup.
From the CommCell Browser, navigate to Client Computers |
<Client>
| DB2.
Right-click the backup set and then click All Tasks
| Restore.
Click the Recover Database tab.
Select To a point in Time.
Select the date and time of the backup you want to restore.
You can perform a SnapProtect backup for DB2 when the database is on a NFS
Volume. However, you will require a root access in the storage device's NFS configuration
to be able to read and write on the accessible DB2 files
i.e., the host on which the NFS Volume is mounted.
Consider the following while performing a SnapProtect backup for data or
databases that reside on a NFS Volume:
The export name on the storage device should be the same as the storage path on
the storage device.
E.g., if the storage path of the storage device is
/vol/Volume/Qtree, use
/vol/Volume/Qtree as the export name and not an alias such as
/ExportName.
You can use the exports both at the root of a NetApp volume and at
subdirectory levels below the root of the volume.
Make sure that the storage device is accessible from the source and proxy machine
(even if they exist in different domains) using the storage device's short name while
mounting NFS exports from the storage device. Make sure to enter the storage
device credentials using its short name. Do not use an IP address or the
fully qualified domain name.
E.g., use a short name for the server such as
server1 or server2.
When using the Solaris Volume Manager, ensure
that a complete disk is used for a metaset. Also, ensure that the
metaset is owned by single host and the ownership of the metaset is
attained before performing the SnapProtect backup operations.
Supported Configurations:
One Physical Volume containing one Logical Volume
One Physical Volume containing one or more Logical Volumes
Multiple Physical Volumes containing one Logical Volume
Multiple Physical Volumes containing one or more Logical Volume
The adjacent diagram summarizes the Volume Manager support for SnapProtect
backup.
Several additional options are available to further refine your backup operations.
The following table describes the additional options:
Option
Description
Related topics
SCSI Reservation
SCSI reservation can be enabled for SnapProtect backup
for all the agents. Use the registry key
nSCSIReserveForSnap
to enable SCSI reservation. Enabling SCSI Reservation prevents other applications
(SCSI3 compliant) from using the reserved SCSI Device (i.e. the mounted
snapshot).
If this option is enabled and the hardware
does not support this type of operation, subsequent data protection
jobs may fail.
The Pre/Post commands for SnapProtect backup
can either be executed on the proxy or the source computer. You can use
the Pre/Post Process tab of the Subclient Properties dialog
box to select where you wish to execute the Pre/Post commands. SnapProtect
backup supports Pre/Post commands for the agents that support it.
Use of Pre/Post Snap commands is not supported when using Data Replicator as the storage array.
For more information on using the Pre/Post
commands, see
Pre/Post
Processes.
View Snapshot Details
You can view the details of a snapshot for an agent, job,
or a snapshot copy. When you right-click any of these entities, you will
be able to browse all the snapshots corresponding to the selected entity.
From the CommCell Browser, right-click the entity that contains
the snapshots you want to browse, and click All Tasks |
List Snaps.
The Snaps created during SnapProtect operation dialog box displays
a list of all the snapshots created for the selected entity and displays important information about each snapshot, including the source
mount path, snap mount path, the storage array, and the source client.
Right-click the snapshot and click Details to view the snapshot
properties.
Select a Job for Backup Copy
You can select a specific job for creating backup copy.
Once selected, the Move Snap to Tape field for the specific job will be
changed to Picked (i.e., the next backup copy operation will move this job
to media).
Right-click a storage policy containing SnapProtect backup jobs,
and then click View Jobs.
Right-click the job and then click Pick for Backup Copy.
Disable a Job for Backup Copy
You can prevent a job from being moved to media. You
can apply this option to those jobs that were previously selected for moving
to media. On selecting this option, the Move Snap to Tape field for the
specific job will be changed to Not Picked (i.e., the next backup copy operation
will not move this job to media).
Right-click a storage policy containing SnapProtect backup jobs
and then click View Jobs.
Right-click the job and then click Do not Backup Copy.
Offline Snap Copy Job Summary Report
Offline Snap Copy Job Summary Report provides
job summary details of backup copy jobs for moving snapshots to media.
