ESXi – Page 94

Nested ESXi Enhancements in vSphere 6.5

10.19.2016 by William Lam // 15 Comments

As many of you have probably heard by now, vSphere 6.5 was just announced at VMworld Barcelona this week and it is packed with a ton of new features and capabilities which you can read more about here. One area that is near and dear to me and has not been covered are some of the Nested ESXi enhancements that have been made in vSphere 6.5.

To be clear, VMware has NOT changed its support stance in vSphere 6.5. Both Nested ESXi as well as general Nested Virtualization is still NOT officially supported. Okay, so thats out of the way now, lets see what is new?

Paravirtual SCSI (PVSCSI) support
GuestOS Customization
Pre-vSphere 6.5 enablement on vSphere 6.0 Update 2
Virtual NVMe support

Lets take a closer look at each of these enhancements.

Paravirtual SCSI (PVSCSI) support

When vSphere 6.0 Update 2 was released, I had hinted that PVSCSI support might be a possibility in the near future. I am happy to announce that this is now possible with running Nested ESXi and having the guestOS as ESXi 6.5. In vSphere 6.5, a new GuestOS type has been introduced called vmkernel65 which is optimized for running ESXi 6.5 in a VM as shown in the screenshot below.

As you can see from the VM Virtual Hardware configuration screen below, both the PVSCSI and VMXNET3 adapter are now the recommended default when creating a Nested ESXi VM for running ESXi 6.5.

Similiar to the VMXNET3 driver, the PVSCSI driver is automatically bundled within the version of VMware Tools for Nested ESXi. That is to say, the drivers are included in the default ESXi image itself and is ONLY activated when ESXi detects that it is running inside of a VM. From a user standpoint, this means there are no additional configurations or installations that is required. You simply select ESXi 6.5 as the GuestOS and install ESXi as you normally would and this will automatically be enabled for you.

The only requirement to leverage this new capability is that BOTH the GuestOS type is ESXi 6.5 (vmkernel65) and the actual OS is running ESXi 6.5. The underlying physical ESXi host can either be ESXi 6.0 or ESXi 6.5. In addition to new virtual hardware defaults, I have also found that the new ESXi 6.5 GuestOS type now uses EFI firmware over the legacy BIOS compared to previous ESXi 6.x/5.x/4.x GuestOS types.

For customers who wish to push their storage IO a bit more for Nested ESXi guests, this is a great addition, especially with lower overhead when using a PVSCSI adapter.

GuestOS Customization

One of the very last capability that has been missing from Nested ESXi is the ability to perform a simple GuestOS customization when cloning or deploying a VM from template running Nested ESXi. Today, you can deploy my Nested ESXi Virtual Appliance which basically provides you with the ability to customize your deployment but would it not be great if this was native in the platform? Well, I am pleased to say this is now possible!

When you go and clone or deploy a VM from template that is a Nested ESXi VM, you will now have the option to select the Customize guest OS option. As you can see from the screenshot below, you can now create a new Customization Spec which is based on the Linux customization spec. The customization only covers networking configuration (IP Address, Netmask, Gateway and Hostname) and only applies it to the first VMkernel interface, all others will be ignored. The thinking here is that once you have your Nested ESXi VM on the network, you can then fully manage and configure it using the vSphere API rather than re-creating the same functionality just for cloning.

To use this new Nested ESXi GuestOS customization, there are two things you will need to do:

Perform two configuration changes within the Nested ESXi VM which will prepare them for cloning. You can find the configuration changes described in my blog post here
Ensure BOTH the GuestOS type is ESXi 6.5 (vmkernel65) and the actual OS is running ESXi 6.5. This means that your underlying physical vSphere infrastructure can be running either vSphere 6.0 Update 2 or vSphere 6.5

You can monitor the progress of the guest customization by going to the VM's Monitor->Tasks & Events using the vSphere Web Client or vSphere API if you are doing this programmatically. Below is a screenshot of a successful Nested ESXi guest customization. If there are any errors, you can take a look at /var/log/vmware-imc/toolsDeployPkg.log within the cloned Nested ESXi VM to determine what went wrong.

I know this will be a very welcome capability for customers who extensively use the guest customization feature or if you just want to quickly clone an existing Nested ESXi VM that you have already configured.

Pre-vSphere 6.5 enablement in vSphere 6.0 Update 2

By now, you probably have figured out what this last enhancement is all about 🙂 It is exactly as it sounds, we are enabling customers to try out ESXi 6.5 by running it as a Nested ESXi VM on your existing vSphere 6.0 environment and specifically the Update 2 release (this includes both vCenter Server as well as ESXi). Although this has always been possible with past releases of vSphere running newer versions, we are now pre-enabling ESXi 6.5 specific Nested ESXi capabilities in the latest release of vSphere 6.0 Update 2. This means when vSphere 6.5 is generally available, you will be able to test drive some of the new Nested ESXi 6.5 capabilities that I had mentioned on your existing vSphere infrastructure. This is pretty darn cool if you ask me!?

Virtual NVMe support

I had a few folks ask on whether the upcoming Virtual NVMe capability in vSphere 6.5 would be possible with Nested ESXi and the answer is yes. Please have a look at this post here for more details.

For those of you who use Nested ESXi, hopefully you will enjoy these new updates! As always, if you have any feedback or requests, feel free to leave them on my blog and I will be sure to share it with the Engineering team and who knows, it might show up in the future just like some of these updates which have been requested from customers in the past 😀

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

09.26.2016 by William Lam // 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.

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

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.

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.

ESXi Thunderbolt Driver to Fibre Channel Storage from ATTO

09.12.2016 by William Lam // 6 Comments

One of the things I always enjoy doing at VMworld, when I am not running around and I have a few minutes to myself, is to check out the VMware Solutions Exchange. This is where you can learn and interact with hundreds of our VMware Certified Partners showcasing their new solutions and innovations that they have built on top of VMware's products.

UPDATE (08/22/17) - ATTO's ESXi Thunderbolt Driver is now officially on the VMware HCL, please see this blog post here for more details.

While walking through the show floor, I had stopped by the ATTO Technology booth who has been a long time partner of VMware in the storage and networking connectivity space. What caught my eye was that they had just released a Beta of an ESXi Thunderbolt Driver in the form of an ESXi VIB that would allow customers to connect their Apple Mac Pro 6,1 using the Thunderbolt 2 interface to an external Fibre Channel storage array. I believe ATTO might be the first vendor ever to produce a Thunderbolt Driver for ESXi. This is really exciting news if you ask me, especially as more and more of our customers are looking to virtualize Mac OS X guests in their Datacenters using vSphere.

Historically, the only option to connect a Mac Pro 6,1 to an external Fibre Channel array was to use something like a Sonnet Chassis. Now, you can potentially connect up to 6 of the built-in Thunderbolt 2 interfaces on the Mac Pro's to your external storage array using this new solution from ATTO. Before I go into some of the details, ATTO did want me to mention that this solution is currently not officially supported by VMware nor is it on VMware's HCL. ATTO will be providing full support on their software as well as VMware's software stack during the duration of the beta program. In terms of official certification on VMware's HCL, I suspect that it will most likely depend on customer demand which would influence whether ATTO applies for an official certification, which again, would be the first of its kind for Thunderbolt.

The way in which this solution works is that you install the ATTO Thunderbolt Driver on your ESXi host and this will allow it to communicate with an ATTO ThunderLink device which provides the Thunderbolt 2 to Fibre Channel connectivity. You have the option of using either the FC2082 which provides 20Gb/s Thunderbolt 2 (2-port) to 8Gb/s FC (2-Port) Device or the FC2182 which provides 20Gb/s Thunderbolt 2 (2-port) to 16Gb/s FC (2-Port) Device. Below is a diagram from the ATTO digital solution brief on Thunderbolt Driver for ESXi which outlines the configuration.

If you are interested in taking part in ATTO's ESXi Thunderbolt Driver Beta program or would like to learn more about the solution, you can reach out directly to Carllene Mowry (*protected email*) who is running the program. For more information be sure to check out the ATTO digital brief on Thunderbolt Driver for ESXi.

Lastly, I was also fortunate to have a quick chat with Carllene and team to get a few additional exclusive tidbits on some of the things the ATTO team is working on next. The first of which is support for the Thunderbolt 3 (aka USB-C) interface to Fibre Channel which will be quite nice for newer platforms that include that interface, including home lab setups such as the Intel NUC. Speaking of Intel NUC, this is just one of the many other platforms that include either Thunderbolt 2 or 3 interfaces. Although the solution today is specifically supporting the Mac Pro, I know ATTO folks are interested to hear from customers on other systems with Thunderbolt interface and providing similiar capabilities.

The other really exciting development that is currently being investigated is support for Thunderbolt 2 or 3 to 10GbE connectivity on ESXi. As you can imagine, this is really going to open up some really cool new use cases, especially around things like VSAN which can easily benefit from this. It is still in early development but from my understanding, ATTO is already seeing a lot of interest in this area as well as how this might work with VSAN. I am hoping I will be able to share more details as this further develops. If any of these updates sounds interesting, do leave a comment to let the ATTO folks know and I will make sure they monitor the thread.