InfoScale™ 9.0 Replication Administrator's Guide - AIX
- Section I. Getting started with Volume Replicator
- Introducing Volume Replicator
- Understanding how Volume Replicator works
- How VVR uses kernel buffers for replication
- Replication in a shared disk group environment
- Using SmartTier with VVR
- Understanding the VVR snapshot feature
- About VVR compression
- Planning and configuring replication
- Before you begin configuring
- Choosing the mode of volume replication
- Planning the network
- Sizing the SRL
- Understanding replication settings for a Secondary
- Configuring VVR in a VCS environment
- Using the primary-elect feature to choose the primary site after a site disaster or network disruption
- Requirements for configuring VVR in a VCS environment
- Example setting up VVR in a VCS environment
- Configuring the agents for a bunker replication configuration
- Section II. Setting up and administering VVR
- Setting up replication
- Creating a Replicated Data Set
- Creating a Primary RVG of an RDS
- Adding a Secondary to an RDS
- Changing the replication settings for a Secondary
- Synchronizing the Secondary and starting replication
- Starting replication when the data volumes are zero initialized
- Displaying configuration information
- Displaying RVG and RDS information
- Displaying information about data volumes and volume sets
- Displaying information about Secondaries
- Displaying statistics with the vrstat display commands
- Collecting consolidated statistics of the VVR components
- Displaying network performance data
- Administering Volume Replicator
- Administering data volumes
- Associating a volume to a Replicated Data Set
- Associating a volume set to an RDS
- Associating a Data Change Map to a data volume as a log plex
- Resizing a data volume in a Replicated Data Set
- Administering the SRL
- Incrementally synchronizing the Secondary after SRL overflow
- Administering replication
- Administering the Replicated Data Set
- Administering Storage Checkpoints
- Creating RVG snapshots
- Using the instant snapshot feature
- About instant full snapshots
- Preparing the volumes prior to using the instant snapshot feature
- Creating instant full snapshots
- About instant space-optimized snapshots
- Creating instant space-optimized snapshots
- About instant plex-breakoff snapshots
- Administering snapshots
- Using the traditional snapshot feature
- Using Veritas Volume Manager FastResync
- Verifying the DR readiness of a VVR setup
- Backing up the Secondary
- Administering data volumes
- Using VVR for off-host processing
- Transferring the Primary role
- Migrating the Primary
- About taking over from an original Primary
- Failing back to the original Primary
- Choosing the Primary site after a site disaster or network disruption
- Troubleshooting the primary-elect feature
- Replication using a bunker site
- Introduction to replication using a bunker site
- Setting up replication using a bunker site
- Using a bunker for disaster recovery
- Replication using a bunker site in a VCS environment
- Configuring and administering VVR using System Management Interface Tool
- Accessing Volume Replicator interface in SMIT
- Setting up a simple Volume Replicator configuration using SMIT
- Displaying configuration information using SMIT
- Administering Volume Replicator using SMIT
- Taking instant snapshot of data volumes of an RVG using SMIT
- Associating a volume to a Replicated Data Set using SMIT
- Transferring the Primary role using SMIT
- Troubleshooting VVR
- Recovery from configuration errors
- Errors during an RLINK attach
- Errors during modification of an RVG
- Recovery on the Primary or Secondary
- Recovering from Primary data volume error
- Primary SRL volume error cleanup and restart
- Primary SRL header error cleanup and recovery
- Secondary data volume error cleanup and recovery
- Tuning replication performance
- SRL layout
- Tuning Volume Replicator
- VVR buffer space
- Tuning VVR compression
- VVR buffer space
- Setting up replication
- Section III. Analyzing your environment with Volume Replicator Advisor
- Introducing Volume Replicator Advisor (VRAdvisor)
- Collecting the sample of data
- About collecting the sample of data
- Collecting the sample of data on UNIX
- Collecting the sample of data on Windows
- Analyzing the sample of data
- About analyzing the sample of data
- Analyzing the collected data
- Understanding the results of the analysis
- Viewing the analysis results
- Recalculating the analysis results
- Installing Volume Replicator Advisor (VRAdvisor)
- Section IV. VVR reference
- Appendix A. VVR command reference
- Appendix B. Using the In-band Control Messaging utility vxibc and the IBC programming API
- Using the IBC messaging command-line utility
- Examples - Off-host processing
- In-band Control Messaging API
- Appendix C. Volume Replicator object states
- Appendix D. Alternate methods for synchronizing the Secondary
- Using the full synchronization feature
- Using block-level backup and Storage Checkpoint
- Using difference-based synchronization
- Examples for setting up a simple Volume Replicator configuration
- Appendix E. Migrating VVR from IPv4 to IPv6
- Migrating VVR to support IPv6 or dual stack
- About migrating to IPv6 when VCS global clustering and VVR agents are not configured
- About migrating to IPv6 when VCS global clustering and VVR agents are configured
- About migrating to IPv6 when VCS global clustering and VVR agents are configured in the presence of a bunker
- Migrating to IPv6 when VCS global clustering and VVR agents are configured in the presence of a bunker
- Appendix F. Sample main.cf files
Example for setting up replication using block-level backup and checkpointing
This example assumes that the RDS has been created using the example procedure.
See Creating a Replicated Data Set for the examples.
You can synchronize the Secondary using block-level backup and checkpointing when the application is active or inactive.
To synchronize the Secondary using block-level backup and checkpointing
- Start a Storage Checkpoint on the Primary:
# vxrvg -g hrdg -c checkpt_presync checkstart hr_rvg
Note down the Storage Checkpoint name you use, that is, checkpt_presync.
- Perform a block-level backup of the data volumes in the Primary RVG.
- End the Primary Storage Checkpoint when the backup is complete:
# vxrvg -g hrdg checkend hr_rvg
- Restore the backup to the Secondary data volumes.
- Use the vxrvg cplist command on the Primary to check whether the Storage Checkpoint you created is still valid.
If the Storage Checkpoint has overflowed, repeat 1 to 4.
The output resembles:
Name MBytes % Log Started/Completed checkpt_presync 10 9 Completed
- Start replication using the Storage Checkpoint:
# vradmin -g hrdg -c checkpt_presync startrep hr_rvg london
- On the Primary, check whether the consistent flag is set on the Primary RLINK using the vxprint command. The RLINK becomes consistent only after the data contained in the Storage Checkpoint is sent to the Secondary. Wait and then issue the following command on the Primary:
# vxprint -g hrdg -l rlk_london_hr_rvg
If the Secondary is consistent, the synchronization was successful.
If the Storage Checkpoint overflows before the Secondary becomes consistent, the synchronization process has failed. Increase the size of the SRL.
See Changing the size of the SRL on the Primary and the Secondary.
Then restart the procedure beginning at step 1.
It is likely that there might be writes beyond the Storage Checkpoint that are yet to be sent to the Secondary after consistent flag is set on the RLINK. Use the vxrlink status command to check whether the RLINK is up-to-date:
# vxrlink -g hrdg status rlk_london_hr_rvg
The same backup and the corresponding Storage Checkpoint can be used to set up additional Secondary hosts while the Storage Checkpoint is still valid. If a Storage Checkpoint has overflowed, its corresponding backup cannot be used to resynchronize the Secondary. Eventually, any Storage Checkpoint that becomes STALE is unusable. There is no warning to indicate that this has occurred. However, the vxrvg cplist command indicates that the Storage Checkpoint has overflowed and hence is unusable.