Recovery Points

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Recovery Point Types


How to Set Up Recovery Points

Manage Recovery Points

Important Considerations


Recovery Point is set of snapshots of the data to preserve a point-in-time on the Destination. This not only affords an extra measure of protection for your data, it also expands the number of options you have when recovering your data.

For any supported configurations snapshot-based Recovery Points can be created and backed up. In addition, Recovery Points can be mounted, and for Windows can also be shared, to make it available to users on the network.

The illustration on the right provides a high-level look at how data flows when creating Recovery Points and backup of Recovery Points.

A Recovery Point is created at the Replication Set level. It will consist of a snapshot of every destination volume used by all the Replication Pairs that comprise the Replication Set.

Here is an example:

repset1 is comprised of the following Replication Pairs:

  • reppair1: destination is F:\repset1_data\reppair1\
  • reppair2: destination is F:\repset1_data\reppair2\
  • reppair3: destination is G:\repset1_data\reppair3\
  • reppair4: destination is H:\repset1_data\reppair4\

Since the destinations used for all of the Replication Pairs in this Replication Set involve three volumes, namely F:, G:, and H:, on the destination computer, each Recovery Point for this Replication Set would contain three snapshots.

Recovery Point Types

Three types of Recovery Points can be used with ContinuousDataReplicator (CDR). They are:

Recovery Points

Recovery Points consist of snapshots created on the destination computer by the specified snapshot engine, without any reference to the state of the source computer. It simply represents a point-in-time on the destination computer, and is thus more useful for file system data than for application data.

Consistent Recovery Points

A Consistent Recovery Point defines a point-in-time in which data is in a consistent state on the source computer. This ensures the data can be restored to that point-in-time. Hence it is more useful for application data than for file system data. Consistent Recovery Points are created as follows:

This process ensures the application can be restored to the exact point-in-time when the marker was placed on the source. Note that for non-integrated applications, CDR will not automatically quiesce the application server, but you can configure this behavior through the use of a quiesce and unquiesce script. When Consistent Recovery Point creation has been specified for a Replication Set, CDR will automatically check for the existence of quiesce/unquiesce batch files. If they are found, the script-based quiescing and unquiescing will be executed in conjunction with the placing of a marker in the Replication Log file on the source. Also, read Application Integration to understand how CDR replicates application.

You can create appropriate batch files using the name and location on the source computer given below. Note that you must use the Replication Set name to uniquely differentiate quiesce/unquiesce batch files from each other, since you may use such batch files for multiple Replication Sets.

Recovery Points for Fan-In Configuration

Recovery Points created for a Fan-In configuration use VSS or ONTAP as the snap engine for creating snapshots. The use of snap engine is based on the destination being used. When the destination is a fixed volume then VSS is used and when the destination is a filer or iSCSI device then ONTAP is used for the creating snapshots. When destination volume is ONTAP LUN, Use ONTAP snapshot for ONTAP LUN destination option should be selected for creating snapshots with ONTAP snapshot engine. In case if option is not selected, VSS snapshot engine will be used.

Consider the following for ONTAP snapshots:


The following are the prerequisites for implementing Recovery Points.

Install Requirements

License Requirements

This feature requires a Feature License to be available in the CommServe® Server.

Review general license requirements included in License Administration. Also, View All Licenses provides step-by-step instructions on how to view the license information.

How to Set Up Recovery Points

The following section provides the steps required to configure and use Recovery Points with CDR, based on a single source and single destination. If your environment uses a different scenario, adjust your steps accordingly.

Perform the following tasks to create Recovery Points:

  1. If you wish to configure Consistent Recovery Points, you must first configure CDR to replicate data.

    See Configure CDR to Replicate Application Data for step-by-step instructions.

  2. For both Recovery Points or Consistent Recovery Points, you must then configure the recovery points.

    See Configure Recovery Points for step-by-step instructions.

  3. Next you must create the Recovery Points.

    For Direct Replication and Fan-Out Configurations, see Create a Recovery Point for step-by-step instructions.

    For Fan-in Configuration, see Create a Recovery Points in a Fan-in Configurations for step-by-step instructions.

You can also optionally perform the following operations:

Manage Recovery Points

All Recovery Points can either be scheduled or created on-demand. Consider the following sections for managing Recovery Points.

Backup Recovery Points

Restore Recovery Points

The backup of Recovery Points or Consistent Recovery Points is performed using the Windows File System iDataAgent, which is also used to perform restore operations. For more information about restoring from a backup, see Restore Data - Windows File Systems.

Delete Recovery Points

When the maximum number of Recovery Points is reached, they are automatically deleted by the system in the order in which it was created, starting with the oldest first. If one of the Recovery Points to be deleted is mounted, shared or in use, the following actions will be performed.

The maximum number is either the maximum number you specified in the Replication Set Properties, or you can configure the maximum number of Recovery Points that exist at any one time (per Replication Set for Windows, or per Replication Pair for UNIX) up to the following system limits:

Obviously, the higher the limit you set, the greater will be the need for hard disk space.

Recovery Points can also be deleted manually, as long as they are unmounted, and for Windows, unshared. The system behavior is slightly different depending on the operating system:

For step-by-step procedures, see Delete a Recovery Point.

Recovering Data from Recovery Points and Backups of Recovery Points

Recovering data from Recovery Points or backups of Recovery Points is similar to Recovery Replicated Data. No additional or special steps are required. For more information on recovering data, see Recover Replicated Data.

Important Considerations

Consider the following when using either type of Recovery Point with CDR.


Consistent Recovery Point for Exchange Data

Replication Pairs for Oracle

If Replications Pairs for Oracle log and database replication are configured to use the same destination volume, the actual number of Recovery Points retained will be the number specified in Maximum Number of Recovery Points divided by two, because separate snapshots will be created for the logs and the database. For example, if you have specified 10 as the maximum number of Recovery Points, but use the same destination volume for the logs and database, only 5 Recovery Points will be retained, with 2 snapshots in each.

Snapshot space requirements

It is essential to ensure that the destination volume specified for each Replication Pair has sufficient space for the maximum number of snapshots that will be created and retained.

For VSS, the cache can be configured using the vssadmin add shadowstorage command from a command line prompt. Refer to Microsoft documentation for details. Note that if the specified volume runs out of space, VSS will delete existing snapshots to make room for the new snapshots, even if your specified maximum number of Recovery Points has not been reached.

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