Nested Virtualization

Do I need additional licenses for Nested ESXi?

05.21.2014 by William Lam // Leave a Comment

The topic of licensing is usually something I try to stay far away from because I have no interest in it and it is usually complex, which ends up hurting my brain. Having said that, one question that I receive every so often from customers who run large number of Nested ESXi instances in their environment is whether or not they need an additional license for a Nested ESXi instance?

The answer to that question can be found in a VMware KB 2009916 that was published last year, here is a quick excerpt:

Customers running nested ESXi/ESX will need to obtain additional licenses for the nested ESXi/ESX. This includes, but is not limited to:

VMware ESXi/ESX running in VMware Workstation or VMware Fusion

VMware ESXi/ESX running in VMware ESXi/ESX

VMware ESXi/ESX running in other third-party hypervisor solutions

I know this might be a bit disappointing to hear, but you should remember that Nested Virtualization and specifically Nested ESXi is not officially supported by VMware. As such, from a EULA point of view, this is just seen as another instance of ESXi being deployed which will require a license. For customers who have an ELA (Enterprise Licensing Agreement) with VMware with an "all you can eat" license agreement, this is not an issue, but for others who do not have such an agreement, here are a couple of tips that may help.

Disclaimer: The information listed below are those of my own personal opinion. For any concerns or clarifications regarding licensing, please reach out to your local VMware account team.

Run ESXi in evaluation mode - Depending on your use case, you may only need your Nested ESXi instance for a short period of time and you can always re-install using the 60 day evaluation
Configure Nested ESXi with single vCPU - Since ESXi is licensed on a per socket basis, you can assign a single vCPU with 2-cores to minimize the licensing impact. For customers who are using vCloud Director and is not on the latest VCD 5.5 release, you may want to import your Nested ESXi VM through vCenter Server as VCD does not support per core allocation in previous releases

If you feel that Nested ESXi should be supported or that there should be a specific SKU or licensed feature for Nested ESXi, be sure to provide this feedback to your local account team with your use cases so it can be fed back to product management.

How to run Nested ESXi on the vCloud Hybrid Service?

05.02.2014 by William Lam // 7 Comments

Today I was granted access to VMware's vCloud Hybrid Service and the first order of business for me of course, was to provision a Nested ESXi VM! After going through the vCHS UI (which is very slick and easy to use by the way) and the vCloud Director UI, I realized the ESXi guestOS type has not been enabled on the backend of the vCloud Director Database. This totally makes sense, as vCHS is a production ready service and they definitely would not want to run anything that is not officially supported.

Having said that, I can see the benefits to customers who would like build out a Nested ESXi environment on vCHS for lab purposes instead of having to manage their own. Some customers even leverage Nested ESXi as part of their development and testing of software and it can be challenging at times to quickly spin up a brand new environment. Instead, they go to vCHS and with just a couple of of clicks in the UI or automatically using the vCloud APIs, provision a couple of Nested ESXi instances for testing. You can easily discard the resources once you are done or keep them running a bit longer.

Having worked with vCloud Director in the past, I knew that you could import an OVF/OVA and I thought maybe I could just import the Nested ESXi OVF templates that I built and potentially workaround vCHS "limitation" 🙂

Disclaimer: Nested ESXi and Nested Virtualization is not officially supported by VMware nor is it supported on vCHS

I tried to upload one of the OVF templates that I built, but it turns out vCloud Director does not supported the Dynamic Disks feature, so I had to perform two additional steps.

Step 1 - Download one of the following Nested ESXi OVF templates

Step 2 - Import the OVF template in an existing vSphere environment and ensure you are doing so using the vSphere Web Client, as some of the properties may not be imported properly

Step 3 - Once deployed, go ahead and re-export the image to an OVF/OVA (I choose OVA as it is a single file) and this will generate the empty VMDKs for you so the image should still be very small (< 1MB)

Step 4 - Login into to your vCHS account and click on your Virtual Datacenter. Select Virtual Machines and then click on Manage in vCloud Director. Import the OVF/OVA that you have just exported

Step 5 - Once the import has been completed, you now have a Virtual Machine that has been configured with the correct guestOS type which should be VMware ESXi 5.x as seen in the screenshot below

Step 6 - At this point, you can either mount an ESXi ISO over your browser or upload it into the vCloud Director Catalog so you can mount it locally and begin your installation of ESXi. Below is a screenshot of 3 Nested ESXi VMs running on vCHS

Note: It looks like some of the advanced VM settings that are part of my OVF template are ignored as part of the vCloud Director import. This means that if you would like to run a Nested VSAN environment on vCHS, you will not be able to rely on the SSD emulation setting but instead, you will need to run through the ESXCLI claim rules to mark particular disks as "SSD" devices. It would have been really nice if vCloud Director would preserve all the advanced VM settings but at least you can still run a Nested VSAN environment.

So there you have it, Nested ESXi running on vCHS! I am kind of curious if this is the first instance of a Nested ESXi VM running on vCHS without having admin access on the backend system?

Note: One limitation to be aware of is that since the backend of vCloud Director is not properly enabled for Nested Virtualization support, this means you will NOT be able to run Nested VMs on top of the Nested ESXi instances. This is due to the lack of having Network Pool which has both Promiscuous & Forge Transmits enabled which is a requirement for proper Nested VMs connectivity. I wonder if vCHS should provide Nested Virtualization capabilities? I know I definitely would like to see it, what do you think? Leave a comment if you have some thoughts on this topic.

UPDATE (05/4/14) - If you wish to run a Nested VSAN environment on vCHS, you will need to take a look at this blog post here on how to "fake" an SSD on one of the devices by using ESXCLI claim rules. The rason for this is that you will not be able to leverage the other method of emulating an SSD device via advanced setting as that requires access to the underlying vSphere environment which you will not have in vCHS.

OVF template for creating Nested ESXi 3 or 32 node VSAN Cluster

04.15.2014 by William Lam // 14 Comments

Last week I had to build a couple of Nested VSAN environments for testing and of course I used my VSAN Nested ESXi OVF template to help expedite the deployment. After deploying the OVF for the third time to get my three Nested ESXi nodes, it hit me. Why am I doing this each time when I know I will need a minimum of three nodes for a proper VSAN environment? Not sure why I did not think of this earlier, but why not create a vApp that contains three Nested ESXi VM templates?

By leveraging the Dynamic Disk feature in OVF, I was able to create two tiny vApps (40KB & 410KB respectively) based off of my original Nested VSAN ESXi OVF template:

The only difference with these OVF templates is that you can now easily an quickly deploy a single OVF that will contain the minimal number of VSAN nodes up to the maximum supported which is 32.

Disclaimer: Nested Virtualization is not not officially supported by VMware, please use at your own risk

Prerequisite:

vSphere Web Client
- To deploy either the single VSAN Nested ESXi OVF template or these new ones, you need to make sure you deploy using the vSphere Web Client. The reason for this is that the lossless OVF import/export feature is only available when using the vSphere Web Client, else you the import will not capture all the settings the OVF template was configured with.
vSphere Cluster w/DRS enabled
- vApp creation is only possible when DRS is enabled

Step 1 - Deploy the OVF template using the vSphere Web Client and make sure you select "Accept extra configuration options" which contains extra parameters needed to run ESXi and VSAN in a nested environment.

Step 2 - Go through the OVF deployment wizard as you normally would. When you get to "Customize Template" you will notice each Nested ESXi VM is in its own Category as seen in the screenshot below. Here you can leave the defaults for a minimal VSAN deployment which contains 2GB disk for ESXi installation, 4GB disk for an "emulated" SSD and 8GB disk for MD or you can specify the size for each disk.

In just a couple of seconds, you will now have a vApp that contains either a 3-node Nested ESXi VM or you can go big and deploy a 32-node Nested ESXi environment.

Note: Please note there maybe other configurations changes such as this one and/or increase in VM resources to run larger VSAN Clusters.

I know these OVF templates will come in handy for myself when needing to quickly deploy a VSAN running in a Nested ESXi environment and hopefully it will also benefit others in the community as well!