Veritas InfoScale™ 8.0.2 Replication Administrator's Guide - Linux
- 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
- VVR event notification
- 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
- 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. Getting started with File Replicator
- Introducing File Replicator
- Administering File Replicator
- Displaying file replication job information
- Section IV. 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 V. 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
How File Replicator works
File Replicator replicates a set of files on a single file system. It replicates the files or a specified consistency group to a single target. The replicated files are sent over the network on a periodic basis with a period ranging from 15 minutes to a 180 minutes. The target is updated to match the current status of the source files as of the most recent start of replication using Storage Checkpoints. The changes since the last replication iteration are efficiently identified using the FCL (File Change Log) and Storage Checkpoints.
A replication job is directional. The job definition includes the source and destination, both host addresses, and the mount points. It also includes the interval at which incremental replication is scheduled. At each interval, a file system point in time image is taken and the file/directory changes are sent to the target as a stream of deltas where it is applied to have the target image mirror the point in time image of the source.
A consistency group consists of an include and exclude path and pattern list. An include list can have both paths and patterns and specifies a combination of files and directories within a file system that needs to be replicated as a single consistent unit. An exclude list specifies files and directories that must not be replicated. Both include and exclude path and pattern lists are optional. If no paths are specified in the include path list and no patterns are specified in the include pattern list, the entire file system is replicated, with the exception of any files or directories which match an exclude path or pattern.
The following directories and files from the root of the file system are not replicated and may not be specified in the exclude list:
lost+found
.placement_policy.xml
quotas
quotas.grp
quotas.64
quotas.grp.64
At system startup, if enabled, the replication scheduler and the replication daemons are started. Once the replication job is started using the vfradmin command, the scheduler daemon enables the FCL if it is not already enabled, takes a file system Storage Checkpoint, and starts the replication process against the newly created Storage Checkpoint. Old Storage Checkpoints are removed once they are no longer useful.
The replication daemon is useful on machines that act as a replication target. It listens for incoming connections and applies the changes on the target file system. After every iteration, a file system Storage Checkpoint is taken. The old Storage Checkpoint is deleted once a new one is created.
The Storage Checkpoints used by VFR are data full checkpoints and will consume extra storage on both the source and the target file systems. Also note that the FCL is enabled by VFR and it is not advisable that you disable some FCL events or disable the FCL entirely. VFR will detect such events and will use a less efficient method to identify the changed files and directories. VFR will also enable the missing FCL events and turn FCL back on.