Async Policy-Based Replication

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Use this information to learn about commands available for Async Policy Based-Replication sessions. To issue a command, go to Session Actions > Commands and click the command.

Table 1. Async Policy-Based Replication commands.
Command	Action
Start H1->H2	Initiates the asynchronous copying of data from H1 to H2 for all volumes in the Volume Group on the storage system. When you initially apply an asynchronous policy to a Volume Group, the storage system starts replication automatically between the source and target storage systems. However, after replication stops due to either a planned or unplanned outage, it becomes necessary for the customer to intervene. They need to restart replication in the correct direction, based on which volumes are serving as the production volumes. The session goes into a Preparing state if any initial synchronization is necessary. Once the sites are synchronized, consistency groups form, and the session enters a Prepared state.
Start H2->H1	Copies data from H2 to H1 asynchronously for all volumes in the Volume Group on the storage system. When you initially apply an asynchronous policy to a Volume Group, the storage system starts replication automatically between the source and target storage systems. However, after replication stops due to either a planned or unplanned outage, it becomes necessary for the customer to intervene. They need to restart replication in the correct direction, based on which volumes are serving as the production volumes. The session goes into a Preparing state if any initial synchronization is necessary. Once the sites are synchronized, consistency groups form, and the session enters a Prepared state.
Failover	Issue this command to failover the session to the target site. This command performs the steps necessary to make the target volumes consistent and available for access as the new primary site. After this command completes, the session state becomes Target Available. When the session is in a Target Available state, it is important that the volumes at both Site 1 and Site 2 are available for writes. The customer must determine which site is considered the production site, and restart replication in the correct direction. If the session suspended, due to a disaster while in the Recovery Test Mode, this command can be issued to allow production to move to the target volumes. Failing over the session while in a recovery test mode will recover the targets to either an older consistency point using the Snapshot created when the Start Recovery Test command was issued, or to a diverged copy of the data which may include updates to the data from the hosts attached to the targets for testing purposes. Note: The session will automatically attempt to restore the targets using the Snapshot created when the Start Recovery Test command was issued. Some levels of the hardware may not support restoring the targets from a Snapshot while Asynchronous Policy Based Replication is defined. On those levels, the failover will recover the targets to a diverged copy of the data. To restore the targets to a Snapshot, remove the Asynchronous Replication policy from the Volume Group and then attempt the restore from the the hardware or in a Snapshot session on the Copy Services Manager server.
Start Recovery Test	Issue this command to place the Volume Group into a Recovery Test mode. After this command completes, the session state becomes Recovery Test Mode and the session status will display as Warning. In this state, the Volume Group will allow the target volumes to be attached to hosts so that Recovery procedures can be tested prior to the event of an actual disaster. While data will continue to be replicated to the target site, consistency will not be maintained and the Recovery Point Objective for the session will continue to increase. When the command is issued the session will automatically create a Snapshot at the target site which can be used in the event that a disaster occurs while in the Recovery Test Mode state. If it becomes necessary to Failover to the target site, the session will attempt to automatically restore the targets to the data in the Snapshot. This will restore the volumes back to the time that the Snapshot was taken.
Stop Recovery Test	Issue this command to place the Volume Group back into an Asynchronous replication state where consistency groups will begin forming again at the target site. After this command completes, the session state becomes Preparing again until consistency is formed and the session state becomes Prepared.
Confirm Production at Site 1	Confirms that you want to establish site 1 as the production site after you issue the Failover command to the session. Once this command is issued, only the Start H1->H2 command is available on the session for restarting replication.
Confirm Production at Site 2	Confirms that you want to establish site 2 as the production site after you issue the Failover command to the session. Once this command is issued, only the Start H2->H1 command is available on the session for restarting replication.
Create Snapshot	Creates a snapshot of all volumes in the volume group on the Production Storage System that is in the associated Snapshot session. The server requeries the hardware to ensure that all volumes in the volume group are contained in the new snapshot. Each snapshot that is created is displayed in the table of snapshots on the session details panel for the session. Hosts cannot attach directly to snapshots. To attach hosts to the snapshots, first create a clone or thin clone of the snapshot.
Create Safeguarded Snapshot	Creates a Safeguarded snapshot of all volumes in the volume group on the Production System that is in the associated Snapshot session. The server requeries the hardware to ensure that all volumes in the volume group are contained in the new safeguarded snapshot. Each safeguarded snapshot that is created is displayed in the table of snapshots on the session details panel for the session and is marked as Yes in the Safeguarded column. Hosts cannot attach directly to snapshots. To attach hosts to the snapshots, first create a clone or thin clone of the snapshot.
Create Recovery Site Snapshot	Creates a snapshot of all volumes in the volume group on the Recovery Site Storage System that is in the associated Snapshot session. The server requeries the hardware to ensure that all volumes in the volume group are contained in the new snapshot. Each snapshot that is created is displayed in the table of snapshots on the session details panel for the session. Hosts cannot attach directly to snapshots. To attach hosts to the snapshots, first create a clone or thin clone of the snapshot.
Create Recovery Site Safeguarded Snapshot	Creates a Safeguarded snapshot of all volumes in the volume group on the Recovery Site System that is in the associated Snapshot session. The server requeries the hardware to ensure that all volumes in the volume group are contained in the new safeguarded snapshot. Each safeguarded snapshot that is created is displayed in the table of snapshots on the session details panel for the session and is marked as Yes in the Safeguarded column. Hosts cannot attach directly to snapshots. To attach hosts to the snapshots, first create a clone or thin clone of the snapshot.
Refresh Thin Clone	Use this command to refresh the data on a selected set of thin clone volumes at the Production Site, with a different Snapshot or Safeguarded Snapshot. When the command is issued, the user selects one of the existing thin clones and then one of the existing Snapshots or Safeguarded Snapshots which will be used to refresh the volumes in the selected thin clone. When the command completes, the existing volumes in the selected thin clone will hold a snapshot of the data at the time of the snapshot that was selected. Using the command allows customers to attach their host systems to a single set of volumes when either testing or processing data from a snapshot.
Refresh Recovery Site Thin Clone	Use this command to refresh the data on a selected set of thin clone volumes at the Recovery Site, with a different Snapshot or Safeguarded Snapshot. When the command is issued, the user selects one of the existing thin clones and then one of the existing Snapshots or Safeguarded Snapshots which will be used to refresh the volumes in the selected thin clone. When the command completes, the existing volumes in the selected thin clone will hold a snapshot of the data at the time of the snapshot that was selected. Using the command allows customers to attach their host systems to a single set of volumes when either testing or processing data from a snapshot.