HP 3PAR Operating System Software - Manual (Page 7)

Virtual Volumes Used with Remote Copy.............................................................................188
Thinly Provisioned Virtual Volumes.................................................................................188
Fully Provisioned Virtual Volumes...................................................................................188
Rules for Creating Remote Copy Virtual Volumes..................................................................189
27 Volume Groups.................................................................................190
Why Use Volume Groups..................................................................................................190
How Volume Groups Work...............................................................................................191
Rules for Forming Volume Groups.......................................................................................191
How Volume Groups Are Named.......................................................................................191
Rules for Adding Snapshots to Volume Groups.....................................................................191
How Volume Groups Are Organized on the Remote Copy Pair...............................................192
Natural Direction of Replication.........................................................................................192
Linking Virtual Volumes in Volume Groups...........................................................................192
Unidirectional Volume Groups.......................................................................................192
Bidirectional Volume Groups.........................................................................................192
28 Volume Group Modes.......................................................................194
Overview of Volume Group Modes....................................................................................194
Synchronous Mode..........................................................................................................194
Advantages of Synchronous Mode................................................................................195
Latency in Synchronous Mode.......................................................................................195
Asynchronous Periodic Mode.............................................................................................195
Advantages of Asynchronous Periodic Mode...................................................................196
29 Synchronization Types and Limits.........................................................197
Types of Synchronization...................................................................................................197
Limits on Volumes that Concurrently Synchronize...................................................................197
Asynchronous Periodic Mode Volume Groups......................................................................198
Full Synchronization.....................................................................................................198
Resychronization.........................................................................................................199
Setting Up Resynchronization for Asynchronous Periodic Mode..........................................201
How to Set the Synchronization Period.......................................................................201
Considerations for Setting the Synchronization Period..................................................201
Synchronous Mode Volume Groups....................................................................................201
Full Synchronization.....................................................................................................201
Resynchronization........................................................................................................202
30 Remote Copy Snapshots....................................................................203
Overview of Snapshots.....................................................................................................203
Why Use Snapshots....................................................................................................203
Volume Space Considerations.......................................................................................203
Snapshots in Synchronous Mode........................................................................................204
Snapshots and Initial Synchronization Failure..................................................................204
Snapshots and Resynchronization..................................................................................204
Snapshots and Resynchronization Failure........................................................................204
Snapshots Taken before or during Disaster Recovery........................................................204
If the Backup System Fails........................................................................................204
If the Primary System Fails........................................................................................204
Snapshots in Asynchronous Periodic Mode..........................................................................205
Snapshots Taken during Initial Synchronization................................................................205
Snapshots Taken during Resynchronization.....................................................................205
Snapshots and Resynchronization Failure........................................................................206
Snapshots Taken before or during Disaster Recovery........................................................206
31 Error Handling..................................................................................207
Timeouts for Remote Copy Failure......................................................................................207
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