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How to limit the number "Logical" CPUs in ESXi?

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Last week I received a very strange customer inquiry in which they would like to limit the number of physical CPU sockets seen by ESXi. As you can imagine, my interest was piqued as this is usually not the type of request you hear from customers looking to actively reduce the overall computing power of their underlying hardware, especially if they have paid for it. After digging into the details a bit more, it turns out this is related to licensing.

The customer is running an application on a VM which is licensed by the total number of underlying physical CPU sockets of the server, regardless if they are actively being used by the application or not. The vendor shall be left nameless but I am sure some of you can make some educated guesses 🙂 The customer was in the process of performing a hardware refresh where they would be moving from a 4 socket CPU to an 8 socket CPU and they would be negatively impacted by this change from a licensing standpoint. I can understand their concerns, they have now just doubled their application licensing cost without actually benefiting from the actual hardware update.

Unfortunately, after a bit more research, I found that it is not possible to reduce or limit the number of physical CPU sockets from ESXi. The only capability that we do have today around this topic is to limit the number of Logical CPUs that ESXi can see. This capability is exposed as an ESXi Advanced Setting called VMkernel.Boot.maxPCPUS and by default, this is set to unlimited as you would expect. What this setting does is takes the total number of logical CPUs that you wish to expose to ESXi and then evenly distributes that across your physical CPU Sockets as best as it can.

You can change this setting using a variety of methods including the vSphere Web Client, vSphere C# Client, ESXi Embedded Host Client, vSphere API which includes ESXCLI & PowerCLI. One alternative which I have seen some postings online about which is the ability to turn off specific CPU sockets for certain hardware platforms by using the system BIOs, having said that, I have not actually seen any real confirmation that this is in fact possible.

Below are screenshots using the vSphere C# & ESXi Embedded Host.

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If you prefer to to use the CLI either locally or remotely, you can run the following ESXCLI commands:

List the current configurations

esxcli system settings kernel list -o maxPCPUS

Set a new configuration

esxcli system settings kernel list -s maxPCPUS -v 4

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Automating vRealize Automation 7 Minimal Install: Part 2 - vRA IaaS Agent Deployment

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In Part 2 of this blog series, we will be looking at automating the installation of the vRA IaaS Management Agent which needs run on a Microsoft Windows system. The IaaS Management Agent installer is provided through the vRA Appliance which you can downloaded by opening a browser to the following URL:

https://[VRA_APPLIANCE_HOSTNAME]:5480/installer/download/vCAC-IaaSManagementAgent-Setup.msi

When installing the agent, you will need to provide information about the vRA Appliance that you wish to register the IaaS Management Agent with. The following Powershell script called installvRAIaaSAgent.ps1 will automatically download the vRA Iaas Management Agent from the vRA Appliance and then perform a silent installation. There are 5 mandatory variables that you will need to edit before running the script and the table below describes each of their functions:

Variable Description
VRA_APPLIANCE_HOSTNAME  Hostname or IP of vRA Appliance
VRA_APPLIANCE_USERNAME  Username of vRA Appliance (default: root)
VRA_APPLIANCE_PASSWORD  Password of vRA Appliance
VRA_APPLIANCE_AGENT_DOWNLOAD_PATH  Path to store vRA Agent (optional)
VRA_APPLIANCE_AGENT_INSTALL_LOG  Path to store vRA Agent install logs (optional)
VRA_IAAS_SERVICE_USERNAME OS username to the vRA IaaS Windows System
VRA_IAAS_SERVICE_PASSWORD OS password to the vRA IaaS Windows System

Here is an example of running the script on my vRA IaaS Windows system:

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In the final part of this series we will take a look at automating the configuration of both the vRA Appliance which includes Horizon SSO and the vRA IaaS Windows system which includes the various IaaS components.

Automating vRealize Automation 7 Minimal Install: Part 1 - vRA Appliance Deployment

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Over the last couple of weeks, I have received numerous requests about automating the deployment of the recently released vRealize Automation 7 (vRA) similar to what I did for vCloud Automation Center 6.0 when it was released. To be honest, I have not spent much time with vRealize Automation as you can see from my last post, it was dated back in 2013. I know there have been some significant improvements in the latest vRA release and perhaps it now officially supports silent or scripted installs like the vCenter Server Appliance (VCSA).

I was a bit bummed to hear that this capability still had not made it into the product which would make streamlining proof of concept and Production deployments a breeze. I mean, why would you want to manually install it if you could automate, right? 🙂 I figure I reach out to one of my vRA Engineering buddies Kim Delgado to see if anything had already been done in this area. She was nice enough to share a couple of resources which cover certain parts of the deployment but nothing that was tying everything together.

I figure I would see what I could re-purpose and try to put together a few simple scripts that would allow anyone to easily stand up a minimal vRA 7 deployment for testing and POC purposes. I normally like prove everything out before publishing but in this case, I figure I would just go with the flow. So far, I have broken down the automation into the following three sections listed below. I have successfully completed Part 1 and Part 2 and I have not attempted Part 3 and Part 4, so I do not know it it will be possible or what issues I might run into.

Note: You can deploy vRA 7 in either a minimal setup which has just the vRA appliance and vRA IaaS system running or in a fully distributed model which they are calling Enterprise. In the series, I will only be covering the minimal deployment. For those interested in a distributed deployment, hopefully you will be able to build upon the scripts that I have created and should be a fun learning exercise for those looking to do more automation.

In part 1 of this series, I will be covering the deployment of the vRA 7 Appliance and have created the following PowerCLI deployment.ps1 script. There are several properties you will need to fill out such as the networking configuration, OS credentials, etc. before you can run the script. Once the script completes, you can verify that the deployment was successful by opening a browser to VAMI interface of the vRA Appliance using the following URL: https://[VRA-HOSTNAME]:5480

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Stay tuned for Part 2 next week where I will be covering how to automate the installation of the vRA IaaS Management Agent.