RVCThe new vSphere Web Client in vSphere 5.5 provides access to the majority of the VSAN management functionalities. However if you are the kind of person who wants to dig deep into VSAN performance in-depth and want to know about what’s going on in the physical disk layers, understand cache hit rates, reasons for observed latencies, etc. then the vSphere Web Client won’t satisfy your thirst in vSphere 5.5. This is precisely where the VSAN Observer comes in.

In this series of articles I will start with an RVC  primer and demonstrate how to get started using the VSAN Observer to satisfy your hunger for detail knowledge about what’s going on within the VSAN cluster and its configuration.

The VSAN Observer is packaged with vSphere 5.5 vCenter Server. The VSAN observer is part of the Ruby vSphere Console (RVC), an interactive command line shell for vSphere management that is part of both Windows and Linux vCenter Server in vSphere 5.5. VMware Support exclusively used the VSAN Observer for early internal VSAN troubleshooting, but the utility is now available to all VMware customers using the new vSphere 5.5.

Note: The VSAN Observer has only been tested on Linux platforms so far.

VSAN Observer requirements

  • Modern web browser for the user interface. Preferably Google Chrome.
  • vCenter Server 5.5. Preferably the vCenter Server Appliance, but the Windows version also works.
  • Option 1 – Deploy RVC inside a production vCenter Server that is managing a VSAN Cluster.
  • Option 2 – Deploy an additional vCenter Server just to have RVC, and remotely manage VSAN clusters.

RVC Deployment Options

Option 1 seems to be the most convenient choice, but it’s important to know that the VSAN Observer opens up an unencrypted and not security-hardened HTTP server and doing so on a production vCenter Server may be against corporate security policies. In such a case, option 2 deploying an extra vCenter Server to run RVC may be a better choice for security compliance purposes.

Option 1 is best suited for lab environments, but its worth mentioning that Option 2 has a property that allows you to download and try out new VSAN Observer versions throughout the Beta program and run them against your VSAN without upgrading.

Using RVC and VSAN Observer

RVC can be used to connect to vCenter Servers regardless of their version (Windows or Linux). When using the vCenter Server Appliance login via SSH and use the following syntax to connect:

  • “rvc <user>@<vcenter-hostname>or<vcenter-ip>”

After a successful login, you are presented with virtual file system, with the vCenter Server at the root as illustrated in the screen shot below.

RVC - Login

The virtual file system is navigated with the use of shell commands such as “cd” and “ls”, as well as tab completion. The structure of the file system simulates the tree views found in the old Windows C# vSphere Client. For example:

  •  run “cd <vcenter-hostname>or<vcenter-ip>”, followed by “cd <datacenter-name>” as illustrated in the screen shot below.

RVC - datacenter

The datacenter level contains the majority of vCenter Server objects, which are presented as separate subfolders:

  • computers (clusters)
  • datastores
  • networks (portgroups)
  • vms (virtual machines)

The use of keyboard characters facilitates and simplifies the navigation of the file system. For example the “~” is used to refer to a current datacenter, e.g:

  • “~/computers” for clusters
  • “~/vms” for VMs.

To learn more about any of the available commands simply run:

  • “<command> –help”

Also use “help” and “help <command-namespace>” to learn more about commands, e.g:

  • “help vm”
  • “help vm.ip”

The VSAN cluster configuration can now be viewed by running the VSAN RVC command “vsan.cluster_info ~/computers/” as illustrated in the screen shot below:


This will be it for now, In Part two of the I will get into the VSAN Observer specifics and user interface. RVC and the VSAN Observer provides an incredible amount flexibility for vSphere overall management as well as VSAN performance and troubleshooting capabilities and for that I thank Christian Dickmann (@cdickmann) for taking the time to help me with RVC and VSAN Observer and contributing to this post.

Christian is not only the brains behind this golden nugget but also a technical lead for VSAN at VMware and the RVC and rbvmomi open source maintainer. Follow him on Twitter, the dude is a straight up genius, seriously!!!!

Stay tune, much more to come on this topic.

 – Enjoy

For future updates, be sure to follow me on Twitter at @PunchingClouds