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)
Analyzing the sample of data
VRAdvisor analyzes the sample data according to parameters that you specify such as available network bandwidth and network outage. In addition, VRAdvisor enables you to perform a What-If analysis by varying the values of the parameters. The output of the analysis gives the network the bandwidth that is required to replicate in synchronous mode, and the SRL (Storage Replicator Log) size that is required for a given bandwidth and for the given outages to replicate in asynchronous mode. The results of the analysis help you to set up an optimum configuration for Volume Replicator. For more information about some of the considerations and formulas that determine the size of the SRL,
VRAdvisor enables you to analyze the data that is collected on any of the supported platforms. For more information,
However, to analyze the data, you must install and use VRAdvisor on a Windows operating system.
Prerequisites:
All the files to be analyzed must be present in a single directory.
The sample data must be available in one of the following formats that VRAdvisor accepts:
vxstat output
diskStats output
VRAdv CSV format (used by VRAdvisor Wizard or the UNIX data collection script)
To analyze the collected data using the VRAdvisor Wizard
- Launch the VRAdvisor Wizard on Windows from Start > All Programs > Veritas > Volume Replicator Advisor > VRAdvisor Wizard or, on Windows 2012 operating systems, from the Apps menu in the Start screen.
- On the Welcome panel, select Analysis, and then click Next.
- On the Directory Specification panel, enter the name of the directory containing the data files to be analyzed. All files to be analyzed must be present in the same directory.
The specified directory must contain the data files and any metadata files that are associated with each data file. The associated metadata and data files must have the same name except for the extension. Metadata files must have the extension .meta.
- On the File Selection panel, VRAdvisor displays the list of files in a table. Select the files to be analyzed.
Note:
Files containing the information from the nodes that use the same network bandwidth for replication should be analyzed together. Otherwise, files should not be selected together. In order for the files to be analyzed together, the data collection for each node must start at the same time.
Provide the disk group name, Node name, and Cluster ID, if necessary.
- On the Block Size and Collection Interval Specification panel, specify the metadata.
If the data was collected using the data collection script for UNIX platforms, the generated files contain metadata such as block size, and data collection interval.
If the files do not contain metadata, because the data was collected using operating system commands or the VRAdvisor Wizard, enter the appropriate metadata:
Specify the block size, if required.
If no timestamps are present in the file, or if VRAdvisor is unable to parse the timestamps, specify the interval that is used during the data collection.
- On the Volume or Disk Selection panel, select the tab for each selected file. For each file, the wizard lists the disks or volumes for which data has been collected.
When selecting disks or volumes, ensure that you do not select:
RAID-5 volumes because these are not supported.
Sub-level volumes (if the volumes are layered volumes). Select only the top-level volumes.
The volume that you intend to use as the SRL.
Drives or volumes containing high-activity data that is not be replicated.
Using VRA to analyze data from drives or volumes containing high-activity data that is not to be replicated, may lead to erroneous results.
Select the volumes or disks to be analyzed, and then click Next.
- The RVG Summary panel displays the disks or volumes that were selected for analysis. The disks or volumes for each analyzed file are grouped under an RVG name.
Click Back to modify the selections, or click Next to continue.
- On the Network Parameters for Analysis panel, specify the parameters that apply to all defined RVGs.
Network Bandwidth Available for Replication indicates the total bandwidth of the network across which you are replicating. Enter the network bandwidth that will be available for replication. Select the unit for the network bandwidth from the drop-down list. The default is 100 Mbps.
Note:
Before specifying the network bandwidth you must also consider the loss of available bandwidth because of the TCP-IP/UDP headers, because VRAdvisor does not handle this.
Network Outage Duration indicates the maximum expected outage times applicable for all defined RVGs. For example, the time during which the network link is unavailable for the network that all the RVGs use for replication. Enter the duration of the network outage in days, hours, or minutes. The default is zero.
Click Next.
- The RVG Specific Parameters panel appears. For each RVG, select the tab, and then specify the following parameters:
Bandwidth Limit indicates the bandwidth throttling for that RVG. The default is 0 (zero), which indicates that no bandwidth limit applies.
Secondary Outage Duration indicates the maximum expected outage times specific to that RVG, for example, the time during which the Secondary host for the RVG is unavailable. Enter the outage duration in days, hours, or minutes. The default is one hour.
Apply to all RVG(s) indicates that the same bandwidth limit and outage duration apply to all RVGs. Select this check box to enable the All tab and disable the RVG-specific tabs.
Click Next.
- The Summary of Inputs panel appears. The Total Outage Duration column shows the sum of the Network Outage Duration and the Secondary Outage for that RVG.
Click Back to modify the parameters, or select Analyze to start the analysis. VRAdvisor displays the results of the analysis for the selected data files.