WilliamLam.com

vSAN Witness using Raspberry Pi 4 & ESXi-Arm Fling

by // 36 Comments

As hinted in my earlier blog post, you can indeed setup a vSAN Witness using the ESXi-Arm Fling running on a Raspberry Pi (rPI) 4b (8GB) model. In fact, you can even setup a standard 2-Node or 3-Node vSAN Cluster using the exact same technique. For those familiar with vSAN and the vSAN Witness, we will need to have at least two storage devices for the caching and capacity tier.

For the rPI, this means we are limited to using USB storage devices and luckily, vSAN can actually claim and consume USB storage devices. For a basic homelab, this is probably okay but if you want something a bit more reliable, you can look into using a USB 3.0 to M.2 NVMe chassis. The ability to use an M.2 NVMe device should definitely provide more resiliency compared to a typical USB stick you might have lying around. From a capacity point of view, I had two 32GB USB keys that I ended up using which should be plenty for a small setup but you can always look at purchasing large capacity given how cheap USB devices are.

Disclaimer: ESXi-Arm is a VMware Fling which means it is not a product and therefore it is not officially supported. Please do not use it in Production.

With the disclaimer out of the way, I think this is a fantastic use case for an inexpensive vSAN Witness which could be running at a ROBO/Edge location or simply supporting your homelab. The possibilities are certainly endless and I think this is where the ESXi-Arm team would love to hear whether this is something customers would even be interested in and please share your feedback to help with priorities for both the ESXi-Arm and vSAN team.

In my setup, I have two Intel NUC 9th Pro which make up my 2-Node vSAN Cluster and then an rPI as my vSAN Witness. Detailed instructions can be found below including a video for those wanting to see vSAN Witness in action by actually powering on an actual workload 😀

[Read more...]

ESXi on Arm Fling is LIVE!

by // 17 Comments


The highly anticipated ESXi on Arm Fling has just been announced and is NOW generally available as a new VMware Fling! Head over to https://community.broadcom.com/flings and be sure to carefully read through the documentation before try out the bits.

History

Although ESXi-Arm was publicly demo'ed at VMworld Europe 2018 during the closing keynote by Ray O'Farrell (former CTO of VMware), the reality was there was a ton more to do before ESXi-Arm could be a reality for VMware customers. The newly formed ESXi-Arm team at VMware has been hard at work these last couple of years working with both Arm and its eco-system in extending hardware standards, firmware standards (open contribution to UEFI), and certification beyond the existing Arm server ecosystem, which enabled us to support platforms like SmartNICs and the ubiquitous Raspberry Pi. This is just a glimpse into what it took to get where we are at today.

I am also excited to share that the Virtually Speaking Podcast crew has invited us back for an exclusive episode featuring both Andrei Warkentin and myself to dive deeper into the development of ESXi-Arm project at VMware. This is an episode you will not want to miss!

Hardware

The ESXi-Arm Fling supports a number of different Arm platforms ranging from a traditional Datacenter form-factor to both Near and Far Edge systems including the highly requested Raspberry Pi (rPI)! With the rPI, only the 4b model will be supported and although both the 4GB and 8GB memory model works with ESXi-Arm. We highly recommend folks invest in the 8GB model to be able to take advantage of more vSphere features and be able to run more workloads.


For a complete list of supported Arm hardware platforms, please refer to the ESXi-Arm documentation.

vCenter Support

For customers with an existing x86 vCenter Server or those that would like to deploy a new vCenter Server, you will be able to attach and manage ESXi-Arm hosts just like you normally would as long as you are using vCenter Server 7.0 or greater.


We expect the majority of vSphere platform features to "just work" like vMotion but there may be some features that may not work or have additional requirements.


For example, to enable vSphere HA and/or vSphere FT, the Fault Domain Manager (FDM) Client VIB must be installed on an ESXi-Arm host. Today, this VIB is distributed as part of vCenter Server and only x86 version of the client is available. We do provide FDM Client VIBs for ESXi-Arm as part of the ESXi-Arm Fling, but support will be limited to vCenter Server 7.0c and 7.0d. For detailed instructions, please refer to the ESXi-Arm documentation.

VMware Tools

VMware Tools for ESXi-Arm GuestOS is not bundled as part of ESXi-Arm Fling, but can be installed. To do so, you will need to compile open-vm-tools for your respective GuestOS. Instructions can be found in the ESXi-Arm Fling documentation and below, you can see a screenshot of VMware Tools for Arm successfully running on Ubuntu 20.04 GuestOS running on ESXi-Arm on the rPI 4.

vSAN Witness

Lastly, a popular use case that has been brought up when ESXi-Arm was initially demo'ed was the use of the rPI as an inexpensive vSAN Witness, which is a fantastic use case for ROBO & Edge locations. I am very happy to share that using an rPI 8GB as a vSAN Witness works! As you can see from the screenshot below, I have two physical Intel NUC 9th Pro configured in a 2-Node vSAN Cluster and I am using the rPI as vSAN Witness 😀


In case this was not clear, this is NOT officially supported but it does demonstrate the viability of this concept and and feedback from the our users would help drive the priority and the potential support for such a configuration. More details will be shared in a future blog post outlining the instructions on using rPI as vSAN Witness. Stay tuned!

As you can see, this is just a small taste of what can be done with the ESXi-Arm Fling and the possibilities are truly endless! The ESXi-Arm team is very excited to see what the community will do with the ESXi-Arm Fling, what type of use cases are you solving or workloads that you are running. Below are a few ways in how you can engage with the ESXi-Arm team and community.

How to tell if an ESXi host is a VSAN Witness Virtual Appliance programmatically?

by // Leave a Comment

I had received this question awhile back but I was only able to get to it recently. If you are not familiar with the VSAN Witness Virtual Appliance and its purpose, Cormac Hogan did an excellent write-up on the topic which you can find it here.

how-to-tell-if-esxi-is-vsan-witness-vm-0
The reason this question came up was that if you were to simply iterate over all ESXi hosts within your vSphere Inventory from an Automation standpoint, you might find a mix of regular ESXi hosts and potentially this new VSAN Witness Virtual Appliance which is basically an ESXi host that runs in a VM (e.g. Nested ESXi). Although, it may look and feel like a regular ESXi host, it is not and the question was how might you go about distinguishing between the two? You can of course setup specific naming standards, folder structure or separate datacenter objects, but you still may accidentally retrieve a VSAN Witness host without even realizing it.

One quick solution is to check for a specific ESXi Advanced Setting called Misc.vsanWitnessVirtualAppliance which will return a value of 1 if it is the VSAN Witness Appliance. Here is a quick PowerCLI snippet which demonstrates how you can access this property:

$vmhost = Get-VMHost -Name 192.168.1.115
Get-AdvancedSetting -Entity $vmhost -Name Misc.vsanWitnessVirtualAppliance

how-to-tell-if-esxi-is-vsan-witness-vm-1
Although the method described above is one quick way to easily identify whether an ESXi host is a VSAN Witness Appliance, it is also limited in the information that it provides you. Another approach is to actually use the new VSAN 6.2 Management API and specifically the Stretched Clustering System APIs to retrieve the associated VSAN Witness host for a given VSAN Cluster. Not only will you get more information about the specific ESXi host providing the VSAN Witness functionality which will allow you to correlate back to your vSphere Inventory, but you will also get additional VSAN Witness configuration such as the preferred Fault Domain, Node UUID and the VSAN Cluster that it is associated with for example.

Here is a quick VSAN Management SDK for Python sample script that I had created called vsan-stretched-cluster-system-sample.py which implements the VSANVcGetWitnessHosts() API method. The script prints out a few of the WitnessHostInfo properties as shown in the screenshot below.

how-to-tell-if-esxi-is-vsan-witness-vm-2
One other option is if you simply just want to know if a given ESXI host is a VSAN Witness host or not, there is also the VSANVcIsWitnessHost() API that simply returns a boolean value. This might useful if you just have a list of ESXi hosts retrieved through the vSphere API and no knowledge of the underlying VSAN Clusters.