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Feedback on default behavior for VM Storage Policy

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Today, the vCenter REST (vSphere Automation) APIs currently does not support the use of VM Storage Policies when relocating (vMotion, Cross Datacenter vMotion & Storage vMotion) or cloning an existing Virtual Machine. Customers have provided feedback that this is something that they would like to see get added to the current REST APIs and while this is being looked at, there were a couple of open questions from Engineering.

The following 2-question survey below is to help us understand what the "default" behavior should be when a Virtual Machine is being relocated or cloned within a vCenter Server and a VM Storage Policy is NOT specified when using the APIs. The reason for this is that our existing APIs for relocate and clone today are very flexible and not everything needs to be specified as part of the relocate or clone API specification. However, due to this flexibility, you may observe different behaviors and we would like to understand what the default behavior should be when some of these paraemters are not specified. In the case where you want to be explicit, you can always specify the VM Storage Policy, but the survey is to understand when it is not specified.

Survey: https://goo.gl/forms/aQjVTly2MmVHeRsp1

Thank you  for taking the time to provide your feedback, this will help us build an easy and robust API when dealing with relocate and clone operations using the vCenter REST APIs.

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)

Quick Tip - OVFTool 4.3 now supports vCPU & memory customization during deployment

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In addition to adding vSphere 6.7 support and a few security enhancements (more details in the release notes), the latest OVFTool 4.3 release has also been enhanced to support customizing either vCPU and/or Memory from the default configurations when deploying an OVF/OVA.

Historically, it was only possible to modify these values if you were deploying to a vCloud Director endpoint using either --numberOfCpus or --memorySize. When deploying to a vSphere endpoint, these settings were not applicable and users would need to perform an additional operation calling into the vSphere API using whatever automation tool of choice to reconfigure the VM after deployment. It was not the end of the world but also not ideal if you simply wanted to make a minor modification to the default OVF/OVA you were deploying. I definitely ran into this a few times where having this functionality would have been very useful and I know number of customers have also shared simliar feedback in the past.

I had asked whether it was possible to support this use case and it looks like we already had an internal feature request added to the OVFTool backlog and with some additional customer feedback, we were also able to get this enhancement added to the latest release.

The existing --numberOfCpus and --memorySize accepts a VM Identifier (usually the name) followed by the value, for example

--numberOfCpus:Foo=4

The VM Identifier is to help with vApp deployments where you may have an OVF/OVA which is composed of multiple VMs of which you would like to customize each VM with different values. To ensure we do not break backwards compatibility, this pattern has also been extended when deploying to a vSphere endpoint. Having said that, most customers that I have talked to who use OVFTool generally deploy an OVF/OVA that is comprised of a single VM. In this case, rather than specifying the name of the VM again which is derived from --name property, you can simply use the wildcard asterisk (*) to simply apply it to all VMs within the OVF/OVA.

Here is an example of deploying a PhotonOS OVA which is configured with a default of 1 vCPU and 2GB memory and as part of our deployment using OVFTool, we will increase both vCPU to 2 and memory to 4GB:

ovftool --acceptAllEulas --name=Foo --numberOfCpus:'*'=2 --memorySize:'*'=4096 photon-custom-hw11-2.0-304b817.ova 'vi://*protected email*@192.168.30.200/VSAN-Datacenter/host/VSAN-Cluster'