Volume Replicator 7.4.1 Administrator's Guide - Windows
- Understanding Volume Replicator
- About Volume Replicator
- Basic Volume Replicator terms
- Building blocks of Volume Replicator
- Understanding replication in the Volume Replicator environment
- Modes of replication
- Understanding data flow in Volume Replicator asynchronous mode
- Managing data during failure and recovery
- Replication concepts
- About using Volume Replicator as a disaster recovery tool
- Understanding how Volume Replicator logs writes to the Replicator Log
- Understanding replication settings for a Secondary
- Measures to protect log overflow and replication latency
- Pausing the replication
- Synchronizing the Secondary
- Understanding Volume Replicator support for FlashSnap
- About Synchronized Snapshots
- Understanding Bunker replication
- Understanding Volume Replicator Support for TCP Multi-Connection
- About Volume Replicator memory monitoring and control support
- About Volume Replicator Graphs
- Setting up replication
- Security considerations for Volume Replicator
- Setting up replication using the Setup Replicated Data Set wizard
- Setting up the Bunker RVG for replication
- Using the VEA Console for Volume Replication Operations
- Monitoring replication
- Interpreting the information in the Volume Replicator views
- Monitoring replication using the VEA console
- Checking replication performance using vxrlink stats
- Administering Volume Replicator
- Adding volumes
- Administering the RVG
- Administering replication
- Managing checkpoints
- Pausing replication using Volume Replicator
- Creating snapshots for the data volumes
- Creating synchronized snapshots using the VSS Snapshot wizard
- Administering Bunker replication
- Performing disaster recovery operation
- Deleting Volume Replicator objects
- Accessing data on Secondary host
- Performing automated system recovery (ASR)
- Alternative methods to synchronize the Secondary faster
- Obtaining statistical information through Volume Replicator Graphs
- Using the command line interface
- Administering the RDS using the vxrds command
- Resizing the data volumes
- Displaying the network statistics for the RLINK
- Administering the RVGs using the vxrvg command
- Displaying information using the vxprint command
- Creating snapshots using the vxsnap command
- Administering replicated volumes using the vxvol command
- Displaying and changing replication ports using the vrport command
- Administering the RVG using the vxedit
- Administering the RVG using the vxassist command
- Tuning Volume Replicator
- Examples: Using the command line
- Example 1: Setting up replication using the command line interface
- Example 3: Using Bunker node for disaster recovery
- Example 4: Using synchronized snapshots to restore data
- Configuring Volume Replicator in a VCS environment
- Components of a VCS cluster
- Illustrating a highly available Volume Replicator setup
- How the agents work
- Configuring the agents
- Working with existing replication service groups
- Configuring Volume Replicator with Hyper-V
- Advanced settings in Volume Replicator
- Troubleshooting Volume Replicator
- Recommendations and checks
- Recovering from problems in a firewall or NAT setup
- Recovering from problems during replication
- Error when configuring the VxSAS Service
- Operation time-out errors
- Problems when configuring Volume Replicator in a VCS environment
- Problems when setting performance counters
- Appendix A. Services and ports
- Appendix B. Using the vxrsync utility
- Appendix C. VR Advisor (VRAdvisor)
Performing intelligent synchronization
Although large volume sizes may be one of the important criteria in determining the time that is taken for Automatic Synchronization to complete, in many cases only about 50 percent of the volumes are used.
This results in the synchronization process sending unused blocks to the Secondary, therefore taking a longer time to complete and causing an overhead on the network bandwidth.
The SwiftSync feature enables Volume Replicator to perform intelligent synchronization by replicating only those blocks that the application uses. In some cases these blocks may just have the file system on them. Because only the used blocks are transferred, the synchronization is much faster and allows for more efficient usage of the available network bandwidth.
Note:
The SwiftSync feature can be used only for volumes with the NTFS or ReFS file systems.
By default, Volume Replicator performs intelligent synchronization for volumes with NTFS or ReFS file systems, however if required you can choose to disable this feature.
Note:
Automatic Synchronization does not maintain the order of writes; therefore, the Secondary is inconsistent until the process is complete. The Secondary becomes consistent after the Automatic Synchronization completes.
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