Metro Global Mirror with Practice commands

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Use this information to learn about commands available for Metro Global Mirror with Practice sessions. To issue a command, go to Session Actions > Commands and click the command.

Table 1. Metro Global Mirror with Practice commands
Command	Action
Enable Copy to Site 1	Run this command and confirm that you want to reverse the direction of replication before you reverse the direction of copying in a failover and failback session.
Enable Copy to Site 2	Run this command and confirm that you want to reverse the direction of replication before you reverse the direction of copying in a failover and failback session.
Flash	This command is available in the following states: Target Available state when the active host is H3 Note: Use this command if the FlashCopy® portion of the Recover command from I3 to H3, fails for any reason. The problem can be addressed; and a Flash command can be issued to complete the flash of the consistent data from I3 to H3. Prepared state when the active host is H1 and data is copying H1 to H2 to I3, or the active host is H2 and data is copying H2 to H1 to H3. Prepared state when the active host is H2 and data is copying H2 to I3. Prepared state when the active host is H1 and data is copying H1 to I3. Use this command if the FlashCopy portion of the Recover command from I3 to H3, fails for any reason. The problem can be addressed; and a Flash command can be issued to complete the flash of the consistent data from I3 to H3. Issuing a Flash command on a Global Mirror Practice session for DS8000® temporarily pauses the formation of consistency groups. Ensure that all I3s are consistent, and then flash the data from I3 to the H3 volumes. After the flash is complete, the Global Mirror session will automatically restart, and the session will begin forming consistency groups on I3. You can then use the H3 volumes to practice your disaster recovery procedures.
Allow Practice Flash	Issued to allow a Flash operation again on a Practice session after it has been suspended with the Prevent Reflash of Practice volume after Flash or Recover option. The Allow Practice Flash command appears in the Preparing or Prepared states only if it is currently preventing the reflash. If the session is Preparing, the Flash command does not display until the session gets to the Prepared state. See Prevent a reflash when practicing disaster recovery for more information on using this command.
HyperSwap	Causes a site switch, equivalent to a suspend and recover for a Metro Mirror with failover and failback individual suspend and recover commands are not available. This command is available only for Copy Services Manager.
RecoverH1	Specifying `H1` makes the H1 volume TargetAvailable. When H1->H2->H3 is run, Metro Global Mirror can move production to either the H2 or H3 set of volumes. Copy Services Manager processing differs, depending on the recovery site. Therefore the site designation is added to the Recover command so Copy Services Manager can prepare for the failback. The FlashCopy creates a consistent copy of the data on the H3 volumes so that an application can recover to those volumes and begin writing I/O. When the FlashCopy is complete, the session reaches a Target Available state, and you can attach your volumes on Site 3.
RecoverH2	Specifying `H2` makes the H2 volume TargetAvailable. When H1->H2->H3 is run, Metro Global Mirror can move production to either the H2 or H3 set of volumes. Copy Services Manager processing differs, depending on the recovery site. Therefore the site designation is added to the Recover command so Copy Services Manager can prepare for the failback.
RecoverH3	Specifying `H3` makes the H3 volume the TargetAvailable. When H1->H2->H3 is run, Metro Global Mirror can move production to either the H2 or H3 set of volumes. Copy Services Manager processing differs, depending on the recovery site; therefore, the site designation is added to the Recover command so Copy Services Manager can prepare for the failback.
Re-enable Copy to Site 1	After you issue a RecoverH1 command, you can run this command to restart the copy to the original the direction of replication in a failover and failback session.
Re-enable Copy to Site 2	After you issue a RecoverH2 command, you can run this command to restart the copy to the original the direction of replication in a failover and failback session.
Re-enable Copy to Site 3	After you issue a RecoverH3 command, you can run this command to restart the copy to the original the direction of replication in a failover and failback session.
Refresh States	Refreshes the states of the role pairs that are in the session (if applicable for the session type) and refreshes the state of the session if it is incorrect. This command queries the states of the copy sets on the hardware. You are not required to run this command under typical circumstances; Copy Services Manager refreshes the states of its sessions through multiple means. However, if you discover an inconsistency between Copy Services Manager and the hardware, you can use this command to enable Copy Services Manager to update itself. This command triggers multiple queries on the hardware, which can impact hardware performance. Do not run this command more frequently than every few minutes in each session. This command is not available if the session is in the Defined state.
Release I/O	Enables the source volume to receive data after a copy relationship is suspended. This command is not displayed if the Release I/O after Suspend property is selected for the session.
Start H1->H2->H3 This command is the Metro Global Mirror initial start command.	This command creates Metro Mirror relationships between H1 and H2, and Global Mirror relationships between H2 and H3. For Metro Global Mirror, this relationship includes the J3 volume to complete the Global Mirror configuration. (The J3 volume role is the journal volume at site 3.) The Start H1->H2->H3 command can be used from some Metro Global Mirror configurations to return to the starting H1>H2>H3 configuration. This command is valid only when the session is in a defined, preparing, prepared, target available, or suspended state.
Start H1->H3	From the H1->H2->H3 configuration, this command changes the session configuration to a Global-Mirror-only session between H1 and H3, with H1 as the source. Use this command in case of an H2 failure with transition bitmap support provided by incremental resynchronization. Because there is not a source host change involved, it can be used when a session is in preparing, prepared, and suspended states. You can use this command to bypass the H2 volume in case of an H2 failure and copy only the changed tracks and tracks in flight from H1 to H3. After the incremental resynchronization is completed, the session is running Global Mirror from H1 to H3 and loses the near-zero data loss protection that is achieved with Metro Mirror when H1->H2->H3 is run. However, data consistency is still maintained at the remote site with the Global Mirror solution. From H2->H1->H3 configuration, this command changes the session configuration to a Global-Mirror-only session configuration between H1 and H3, with H1 as the source. Use this command when the source site has a failure and production is moved to the H1 site. For example, for an unplanned HyperSwap®. The Global Mirror session is continued. This is a host-volume change so this command is valid only when you restart the H1->H3 configuration or from the TargetAvailable H2->H1->H3 state.
Start H2->H3	From the H1->H2->H3 configuration, this command moves the session configuration to a configuration between H2 and H3, with H2 as the source. Use this command when the source site has a failure and production is moved to the H2 site. For example, for an unplanned HyperSwap. The Global Mirror session is continued. This is a host-volume change so this command is valid only when you restart the H1>H3 configuration or from the TargetAvailable H2->H1->H3 state. From the H2->H1->H3 configuration, this command changes the session configuration to a configuration between H2 and H3 with H2 as the source. Use this command in case of an H1 failure with transition bitmap support provided by incremental resynchronization. Because there is not a source-host change involved, this command can be used when the session is in the preparing, prepared, and suspended states. The Start H2->H1->H3 command can be used to return to the starting H2->H1->H3 configuration.
Start H2->H1->H3 This command is the Metro Global Mirror start command.	This configuration completes the HyperSwap processing. This command creates Metro Mirror relationships between H2 and H1 and Global Mirror relationships between H1 and H3. For Metro Global Mirror, the J3 volume completes the Global Mirror configuration.
Start H3->H1->H2	After a recovery to H3 is completed, this command sets up the hardware to allow the application to begin writing to H3, and the data is copied back to H1 and H2. However, issuing this command does not guarantee consistency in the case of a disaster because only Global Copy relationships are established to cover the long-distance copy back to site 1. To move the application back to H1, you can issue a suspend while in this state to drive all the relationships to a consistent state and then issue a freeze to make the session consistent. You can then issue a Rcover followed by a Start H1->H2->H3 to go back to the original configuration.
SuspendH2H3	Pauses the Global Mirror master session, which causes the session to stop forming consistency groups, and suspends the H2 to H3 Global Copy pairs. If you are using a System Storage DS8000: The Suspend command invokes a pause command for IBM® DS8000. The pause command that is invoked depends on the IBM DS8000 microcode level. If the following conditions are true, the Suspend command invokes a command that is equivalent to the IBM DS8000 command pausegmir -withsecondary: All primary volumes that are in the session are on a IBM DS8000 storage system with a microcode level that includes the pause with secondary consistency option. To determine whether this option is available for your storage system, see the IBM DS8000 documentation for the microcode level that you are using. The pause with secondary consistency option is enabled on the storage system. If these conditions are not true, the Suspend command invokes a command that is equivalent to the IBM DS8000 command pausegmir. Both commands temporarily pause the formation of consistency groups after the current consistency group is formed. However, the command for a pause with secondary consistency creates a consistent data set on the secondary volumes. If you do not want to suspend the Global Copy pairs when a Global Mirror session is suspended, open the rmserver.properties file in the `install dir`\liberty\wlp\usr\servers\csmServer\properties directory on distributed systems, or the `path_prefix`/opt/IBM/CSM/wlp/usr/servers/csmServer/properties directory on z/OS®, and add the following property: `csm.server.sus_gc_pairs_on_gm_pause = false` Tip: The pause with secondary consistency option requires that the Global Copy pairs are suspended. If you do not want to use the pause with secondary consistency option for storage systems on which the option is enabled, set the csm.server.sus_gc_pairs_on_gm_pause property to false.
SuspendH1H3	Pauses the Global Mirror master session, which causes the session to stop forming consistency groups, and suspends the H1 to H3 Global Copy pairs. The information that is specific to IBM DS8000 in the previous description for the SuspendH2H3 command is also applicable to this command.
Terminate	This command terminates all copy relationships on the hardware.
TerminateH3I3	Removes the FlashCopy relationships after a Flash command is issued. When you use Extent Space Efficient (ESE) volumes for your practice volumes (H3), it is recommended to set the No Copy option on the H3I3 role pair. When No Copy is set, data will only be physically written to H3 when a track is updated on I3. If the practice copy of the data is no longer needed, this command can be run to remove the FlashCopy relationship from I3 to H3, to prevent the relationship from consuming backend space. Notes: If the command is issued, H3 will no longer hold a consistent logical copy of the data until the next Flash or Recover is issued. This command is only available for DS8000 practice sessions while in the Preparing, Prepared, or Suspended states. This command is not available while in the Defined or Target Available states.