How VRAdvisor Works

Using VRAdvisor for planning involves collecting a sample of data that represents the application write rate and analyzing this sample of data based on factors, such as the network bandwidth and network outage. VRAdvisor considers the worst case situations when analyzing data, which results in an optimum configuration for VVR. Working with VRAdvisor involves:

  Data Collection

  Data Analysis

  What-if Analysis

Data Collection

VRAdvisor uses a sample of data for analysis; the sample of data must be available in an appropriate format required by VRAdvisor. To collect a sample of data that represent the application write rate, we recommend that you collect the sample of data for a period of seven to fourteen days. Make sure that the collection period includes times of peak usage for your application, so that the collected data reflects your environment.

In the data collection mode, VRAdvisor collects the sample of data in the appropriate format required by VRAdvisor. You can also collect the sample of data using commands. The commands that can be used to collect the sample of data include vxstat, iostat, and lvmstat. If the data is collected using commands, you may need to use the scripts provided with VRAdvisor to convert the data to the appropriate format required by VRAdvisor. For more information, see Collecting the Sample of Data.

Data Analysis

In the data analysis mode, VRAdvisor analyzes the sample of data that you have collected, based on the following factors specified by you:

• Available network bandwidth
• Maximum expected downtime for the Secondary hosts
• Maximum expected downtime for the network connection
• Frequency of Secondary backups

After analyzing the data, VRAdvisor displays a graphical as well as textual representation of the results in a separate window. For more information, see Analyzing the Sample of Data.

What-if Analysis

The What-if analysis feature enables you to perform additional calculations, to plan for future requirements or alternative scenarios. You can vary the parameters and recalculate the results according to different criteria. For example, you can vary the network bandwidth parameter to see what effect it would have on the SRL size. Or, you can specify a potential SRL size and see how much network bandwidth would be required for that SRL size. For more information, see Analyzing the Sample of Data.