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How to use and interpret performance statistics collected using vSAN Observer (2064240)

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This article provides steps to launch, collect, and display vSAN Observer performance charts and information for VMware vSAN.

vSAN Observer is a monitoring and troubleshooting tool for Virtual SAN. It is designed to:
  • Monitor performance statistics for a vSAN Cluster
  • Provide access through a web browser
  • Capture the statistics for customer use or for VMware
For more information, see the Getting started with the vSAN Observer section in the Diagnostics and Troubleshooting Reference Manual.


vSAN Observer is a feature of the Ruby vSphere Console (RVC).

To launch vSAN Observer:
  1. Log in to the Ruby vSphere Console (RVC) on your vCenter Server Appliance through SSH and run this command:

    rvc username@localhost

    Note: For vCenter Server running on Windows, run this batch file to launch RVC:

    • For vSAN 6.x: %PROGRAMFILES%\VMware\vCenter Server\rvc\rvc.bat
    • For vSAN 5.5: %PROGRAMFILES%\VMware\Infrastructure\VirtualCenter Server\support\rvc\rvc.bat

  2. Enter the user password, if prompted.
  3. Run the cd command to navigate to your vCenter Server directory.
    For example, localhost:

    cd localhost

  4. Run the cd command to navigate to the data center for your vSAN environment.
    For example, vSAN-DC:

    cd vSAN-DC

  5. Run this command to enable live monitoring for a cluster:

    Note: The cluster in this example is named vSAN-Cluster ~/computers/vSAN-Cluster --run-webserver --force

  6. To view the live statistics in a web browser, point the browser URL to your vCenter Server hostname / IP Address with the port number specified in the output of step 5.

     For example, on port 8010:


Additional Information

For more information on the following topics, see the corresponding section in the Diagnostics and Troubleshooting Reference Manual.
  • Usage examples and explanations of vSAN Observer statistics analysis - Getting started with vSAN Observer section
  • Troubleshooting using vSAN Observer - vSAN Observer Case Studies section
  • Additional options available for vSAN Observer - vSAN Observer command line options section
  • Launching the vSAN Observer - Launching vSAN Observer section

Additional options for vSAN Observer

 Output file path. For example, /tmp.
 Port number for live statistics.

 Note: The default port is 8010.
 Run the live statistics.
 Apply force means to forgo any warning messages about the action and proceed.
 Keep observed statistics in memory even when commands ends. This command allows you to resume later.
 Generates an HTML bundle after completion. Pass a location.
 Interval value (in seconds) in which to collect statistics.

 Note: The default value is 60.
 Maximum number of hours to collect statistics. This command caps memory usage.

 Note: The default value is 2.
 Runs until stopped. Every --max-runtime intervals retires a snapshot to disk. Pass a location.

 Example: ~/computers/VSAN --run-webserver --force --generate-html-bundle / --interval 30 --forever
 Does not use HTTPS and does not require a login. Useful if connection over HTTPS is not possible.

 Warning: Insecure, only use if connection over https is not possible.


To generate a performance statistics bundle over a one hour period at 30 second intervals for a vSAN cluster named vSAN and save the generated statistics bundle to the /tmp folder, run this command: ~/computers/vSAN --run-webserver --force --generate-html-bundle /tmp --interval 30 --max-runtime 1

For assistance in calculating a maximum IOPS value and checking if your SSD is a performance bottleneck, use vSAN calculator spreadsheet which is available in the attached file.


vSAN Observer, Ruby vSphere Console, performance statistics

See Also

Update History

01/15/2015 - Added 2 new options for vSAN Observer to the table in Additional Info section 03/12/2015 - Added vSAN 6.0 to Products. 08/09/2016 - Added vSAN 6.1 and 6.2 to Products. 08/10/2016 - mkhalil - Corrected URL to use https only. 11/15/2016 - Added vSAN 6.5 to Products. 04/18/2017 - Added vSAN 6.6 to Products.


Request a Product Feature

To request a new product feature or to provide feedback on a VMware product, please visit the Request a Product Feature page.


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