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Using ESXi Kickstart %firstboot with Secure Boot

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If you install ESXi via a Kickstart script and make use of the %firstboot option to execute commands on the first boot of the ESXi host after installation, you should be aware of its incompatibility with the Secure Boot feature. If you install ESXi where Secure Boot is enabled, the Kickstart will install ESXi normally only execute up to the %post section. However, it will not execute the %firstboot scripts and if you look at the /var/log/kickstart.log after the host boots, you should see the following message:

INFO UEFI Secure Boot Enabled, skipping execution of /var/lib/vmware/firstboot/001.firstboot_001

If you have Secure Boot enabled, %firstboot is not supported. The reason for this is Secure Boot mandates only known tardisks which can hold executable scripts, and a kickstart script is an unknown source so it can not run when Secure Boot is enabled. If you wish to continue using %firstboot scripts, the only option is to disable Secure Boot and then re-enable it after the installation. A preferred alternative is to convert your %firstboot logic into an external script which can then be applied using the vSphere API (recommended method) and this way you can still customize your ESXi host after the initial installations. I have already filed an internal documentation bug to add a note regarding Secure Boot and %firstboot, hopefully that will roll out with the net documentation refresh.

OVFTool and VMware Cloud on AWS

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Recently, I had noticed a number of questions that have come up regarding the use of OVFTool with the VMware Cloud on AWS (VMC) service. I had a chance to take a look at this last Friday and I can confirm that customers can indeed use this tool to import/export VMs into VMC whether they are from a vSphere/vCloud Director-based environment or simply OVF/OVAs you have on your desktop. Outlined below are the requirements and steps that you must have setup before you can use OVFTool with VMC. In addition, I have also include an OVFTool command snippet which you can use and adapt in your own environment.

Requirements:

  1. You must setup VPN connection between your onPrem environment and the Management Gateway on VMC (direct internet access to ESXi is not supported)
  2. Configure the VMC Firewall to allow access between your onPrem and VMC's ESXi host on port 443 (data transfer occurs at ESXi host level)
  3. Specify the Workload VM Folder as a target
  4. Specify the Compute-ResourcePool Resource Pool as a target
  5. Specify the WorkloadDatastore Datastore as a target

Instructions:

Step 1 - Create a Management VPN connection, please see the official documentation here for more details.

Step 2 - Create a two new Firewall Rules that allow traffic from your onPrem environment to both vCenter Server and ESXi host on port 443. vCenter Server will obviously be used for UI/API access and for ESXi, this is where the data traffic transfer will take place.


Step 3 - Construct your OVFTool command-line arguments and ensure you are using the VM Folder "Workloads", Resource Pool "Compute-ResourcePool" and Datastore "WorkloadDatastore" as your target destination since the CloudAdmin user will have restrictive privileges within VMC.

Here is an example command to upload an OVA from my desktop to the VMC vCenter Server:

ovftool.exe `
--acceptAllEulas `
--name=William-To-The-Cloud `
--datastore=WorkloadDatastore `
--net:None=sddc-cgw-network-1 `
--vmFolder=Workloads `
C:\Users\primp\desktop\William.ova `
'vi://*protected email*:*protected email*/SDDC-Datacenter/host/Cluster-1/Resources/Compute-ResourcePool/'

Note: OVFTool also supports the ability to specify a VM that is residing in your vSphere environment as a source, so you do not have to export it locally to your desktop and you can directly transfer it (your client desktop acting as a proxy) to VMC.

Here is the output from running the above command:


Once the upload has completed, you should see your new VM appear in your vSphere Inventory

 

How do you "log a reason" using PowerCLI when rebooting or shutting down ESXi host?

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I am sure many of you have seen this UI prompt asking you to specify a reason before issuing a reboot or shutdown of an ESXi host and I assume most of you spend a few seconds to type in a useful message and not just random characters, right? 😉


Have you ever tried performing the same reboot or shutdown operation using the vSphere API or PowerCLI (which leverages the API)? Have noticed, there is not a way to specify a message like you can in the UI?

Here is a table of the PowerCLI cmdlets and the respective vSphere API that is used to perform these two operations:

Operation Cmdlet vSphere API
Reboot  Restart-VMHost  RebootHost_Task
Shutdown  Stop-VMHost  ShutdownHost_Task

When looking at either the PowerCLI and/or vSphere API documentation, we can confirm that there are no fields to specify a message which can lead to an assumption that this is simply not possible or that the functionality might be provided by a private API. Fortunately, this is not the case and the functionality is in fact in the public vSphere API and has been for quite some time.

When you specify a message prior to rebooting or shutting down, this message is actually persisted and implemented as an Event within vCenter Server as shown in the screenshot below.

Instead of being able to specify a message that is only applicable to an ESXi host, I believe the original vSphere API designers thought that this functionality could also be useful and applied more broadly across any number of the vSphere Inventory objects, not just ESXi hosts. As such, this functionality which the vSphere UI uses is provided by the LogUserEvent() method which is part of the EventManager API. Customers or solutions can leverage this mechanism to log custom user defined events which is then persisted with the lifecycle fo the vSphere Inventory Object or as far back as your retention period for vCenter Server Events.

Going back to our original question, if you want to specify a message prior to rebooting or shutting down an ESXi host, the following snippet below demonstrates the use of the vSphere API via PowerCLI:

$eventManager = Get-View eventManager
$vmhost = Get-VMHost -Name 192.168.30.11
$message = "This message will be logged"

$eventManager.LogUserEvent($vmhost.ExtensionData.MoRef,$message)