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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 😀

VMXNET3 driver now included in Mac OS X 10.11 (El Capitan)+

10.01.2016 by William Lam // 15 Comments

Yesterday I received a pretty interesting comment from one of my Twitter followers @NTmatter who wrote:

@lamw Just noticed that OSX has a VMXNET3 driver. Have to edit the vmx file to actually use it, but it's there! AppleVmxnet3Ethernet.kext

— Thomas Johnson (@NTmatter) September 30, 2016

This is a pretty neat find because currently today, the only network adapter that is functional with an Apple Mac OS X guest running on either VMware vSphere or Fusion is the e1000{e} driver. This update was definitely news to me and after sharing it internally to see if I could find some more details, it turns out this news also came as surprise to the folks internally. Darius, one of the Engineers who I frequently reach out to on Apple related topics did some digging and found out that Apple started to bundle this VMXNET3 driver starting with Mac OS X 10.11 (El Capitan) release. You can find the driver located in /System/Library/Extensions/IONetworkingFamily.kext/Contents/PlugIns/AppleVmxnet3Ethernet.kext

Disclaimer: Given that this VMXNET3 Mac OS X driver was not developed by VMware nor has it been tested by VMware, it currently would not be officially supported by VMware.

If you wish to try out the VMXNET3 driver, you will need to install Mac OS X 10.11 or newer on a VM running on vSphere or Fusion. By default, the only available network adapter type is e1000{e}. To add a VMXNET3 network adapter, you can either manually tweak the .VMX file or you can easily add it by using either the vSphere Web/C# Client or ESXi Embedded Host Client. Below are the instructions on configuring the VMXNET3 network adapter for your Mac OS X guests.

Step 1 - Remove the existing network adapter and then temporarily change the GuestOS type to "Other" (no need to save setting, just update it in VM reconfigure wizard) so that you will be allowed to add a VMXNET3 network adapter. Once you have added it to the VM reconfigure wizard, go ahead and toggle back the GuestOS type to Mac OS X 10.10 and then save the settings as shown in the screenshots below.

Step 2 - Open a terminal inside of the Mac OS X guest and run the following command to load the VMXNET3 driver:

sudo kextload /System/Library/Extensions/IONetworkingFamily.kext/Contents/PlugIns/AppleVmxnet3Ethernet.kext

Step 3 - You can verify that the VMXNET3 driver was successfully loaded by running the following command:

kextstat | grep -i vmxnet3

Once the driver has been loaded, you should now have networking connectivity to your Mac OS X VM using the VMXNET3 network adapter. Below is a screenshot of the system info showing the VMXNET3 network adapter.

In addition to having an optimized networking when using the VMXNET3 driver, the other benefit is being able to get a link speed of 10GbE which is something customers have been inquiring about when virtualizing Mac OS X guests. Below is a screenshot of the media link shown in this Mac OS X 10.11 guests.

Although this a great development for Apple customers who uses VMware vSphere and Fusion, it also does raise an interesting question on whether Apple would be officially supporting this VMXNET3 driver going forward? If I do receive any more details on this, I will update the article. Until then, you can play with this new capability if you are running Mac OS X 10.11 or greater on VMware. Big thanks to Thomas for this great find and sharing it with the VMware Community!

How to check the size of your Config + Stats, Events, Alarms & Tasks (SEAT) data in the VCDB?

09.29.2016 by William Lam // 6 Comments

I think many of you know that I am not a fan of anyone poking around in the vCenter Server Database (VCDB) and having to manually craft SQL queries to retrieve information about their vSphere environment. This is especially true when you can easily and painlessly retrieve all of this information by simply using the vSphere API.

Having said that, there is one use case that is currently not available today in the API, yet. The use case that I am referring to is having better visibility into the storage utilization of our VCDB for things like the Core inventory configuration as well as the Stats, Events, Alarms and Tasks (SEAT) data which generally makes up the bulk of the VCDB data. Some of the benefits to having this information includes understanding the size of your VCDB given your current inventory size + data retention policy, whether or not you should consider reducing/truncating your dataset and even ensuring that vCenter Server rollup jobs have properly ran by simply getting visibility into the current storage footprint of your VCDB.

The other really nice benefit of having this information for those looking to use the recently released VCSA Migration Tool (migrating from Windows vCenter Server to the vCenter Server Appliance) is that it can be used to help calculate the estimated amount of downtime that is required for the migration to complete. The process is currently outlined in the following VMware KB 2146420 which requires customers to manually run a specific SQL query to retrieve the specific tables within the VCDB, perform some basic arithmetic with the results and then plugging them into an excel spreadsheet to provide the time estimations for migration.

UPDATE (10/20/16) - For customers already on the VCSA, you can also perform this query for vPostgres DB by taking a look at this blog post here.

Note: The migration time estimates from VMware are just that, estimates. There are many other factors such as source and destination hardware capabilities, network and storage bandwidth that may influence the amount of time a migration may take. It is recommended that customers use the estimates as guidance and still add a time buffer to their maintenance window.

To help simplify the consumption of the KB, I have created a small PowerShell script called Get-VCDBUsage.ps1 which will allow you to remotely connect to your VCDB (assuming you have enabled remote connectivity) to execute the correct SQL query based on your database platform and provide you with the results. The script also includes an optional parameter which will automatically take the results and calculate the estimated amount of downtime required for migrating from your Windows based vCenter Server to the VCSA. This makes gathering the information about your VCDB quite easy without having to manually go through the KB which can be challenging if you have a large amount of vCenter Servers.

The script supports the following 3 modes:

Running "locally" on the Microsoft SQL Server DB (requires Windows PowerShell Extensions for SQL Server as I rely on the Invoke-Sqlcmd cmdlet)
Running "remotely" connected to the Microsoft SQL Server DB
Running "remotely" connected to the Oracle DB (requires Oracle ODAC Client to be installed on the Windows system running the script)

For the first mode, you only need to specify the dbType, connectionType and dbInstance parameters as it will use the existing local ODBC connection so you do not have to provide any DB credentials. Here is an example command:

Get-VCDBUsage -dbType mssql -connectionType local -dbInstance VCDB

For the second mode, you will need to specify the dbType, connectionType, dbServer, dbPort, dbInstance, dbUsername and dbPassword parameters as you will be connecting remotely and the additional DB information will be needed. Here is an example command:

Get-VCDBUsage -dbType mssql -connectionType local -dbServer sql.primp-industries.com -dbPort 1433 -dbInstance VCDB -dbUsername sa -dbPassword VMware1!

Here is a screenshot of what the output would look like whether you run this against a VCDB running on either Microsoft SQL Server or Oracle system. As you can see, you get a nice break down of the 4 more interesting tables: Core configuration, Alarm, Events and Stats data.

If you wish to also calculate the estimated VCSA migration time, you simply just need to append the -migration_type parameter which accepts a value of option1 or option2. When performing the Windows vCenter Server to VCSA Migration, customers have the option of either only migrating the Configuration + Alarm data which I am referring to as Option 1 (default) or you can migrate all data which includes Configuration + Alarm + Event + Stats which I am referring to as Option 2. By simply changing the parameter in the script, you can get an idea of the time estimate as well as the amount of data (in GB) that would be migrated. Here is an example command:

Get-VCDBUsage -dbType mssql -connectionType local -dbServer sql.primp-industries.com -dbPort 1433 -dbInstance VCDB -dbUsername sa -dbPassword VMware1! -migration_type option1

Here is a screenshot of what the output would look like with the additional parameter.

As you can see, you can easily run this script non-disruptively against your VCDB and assess the amount of data that could potentially be migrated as well as the amount of downtime required for a given migration scenario. This is also a great time to consider whether or not you need all of this data, especially when it comes to the Performance Stats. For Tasks/Events, this data is generally useful for auditing purposes and some of our customers must retain a certain amount for compliance purposes. However, for the Performance Stats, this information may not be as useful as some of you may think. As vCenter Server performs its daily, weekly and monthly rollup jobs, the statistics are continuously averaged out to the point where the granularity of the original data points are pretty lost. This means that you end up storing a ton of data that is really not all that useful. For fine grain historical stats, solutions like vRealize Operations Manager should be considered and vCenter Server should really be used for short term historical stats and quick ease of access for troubleshooting purposes. For more details on calculating the estimated amount of downtime for migration, please refer to VMware KB 2146420.

One last note, as you may have noticed from the screenshot or running the script that at the end of the output there is a question asking if you would like to compare your VCDB stats with others. If you do decide to share the information(completely optional) which only includes the size for the each of the tables and number of rows that will be sent off to a public github repository https://github.com/migrate2vcsa. If we get enough submissions, we may do some fun things with the data and report back to the community. The data is anonymous and it might be interesting to see how your data set compares to others.