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Troubleshooting tips for configuring vSphere with Kubernetes

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With more and more folks trying out the new vSphere with Kubernetes capability, I have seen an uptick in questions both internally and externally around the initial setup of the infrastructure required for vSphere with Kubernetes but also during the configuration of a vSphere Cluster for Workload Management.

One of the most common question is why are there no vSphere Clusters listed or why a specific vSphere Cluster is showing up as Incompatible? There are a number of reasons that this can occur including vCenter Server not being able to communicate with NSX-T Manager to retrieve the list of NSX pre-checks which would cause the list to either be empty or listed as incompatible. Not having proper time sync between vCenter Server and NSX-T which can also manifest in a similar behavior among other infrastructure issues.


Having ran into some of these issues myself when developing my automation script, I figure it might be useful to share some of the troubleshooting tips I have used when trying to figure out what is going on whether that is during the initial setup or actually deploying workloads using vSphere with Kubernetes.

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Deploying a minimal vSphere with Kubernetes environment

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A very useful property of automation is the ability to experiment. After creating my vSphere 7 with Kubernetes Automation Lab Deployment Script, I wanted to see what was the minimal footprint in terms of the physical resources but also the underlying components that would be required to allow me to still a fully functional vSphere with Kubernetes environment.

Before diving in, let me give you the usual disclaimer 😉

Disclaimer: This is not officially supported by VMware and you can potentially run into issues if you deviate from the official requirements which the default deployment script adheres to out of the box.

In terms of the physical resources, you will need a system that can provision up to 8 vCPU (this can be further reduced, see Additional Resource Reduction section below), 92GB memory and 1TB of storage (thin provisioned).


which translates to following configuration within the script:

  • 1 x Nested ESXi VM with 4 vCPU and 36GB memory
  • 1 x VCSA with 2 vCPU and 12GB memory
  • 1 x NSX-T Unified Appliance with 4 vCPU and 12GB memory
  • 1 x NSX-T Edge with 8 vCPU and 12GB memory

Note: You can probably reduce memory footprint of the ESXi VM further depending on your usage and the VCSA is using the default values for "Tiny", so you can probably trim the memory down a bit more.

Another benefit to this solution is by reducing the number of ESXi VMs required, it also speeds up the deployment and in just 35 minutes, you can have the complete infrastructure fully stood up and configured to try out vSphere with Kubernetes!


The other trick that I leveraged to reduce the amount of resources is by changing the default number of Supervisor Control Plane VMs required for enabling vSphere with Kubernetes. By default, three of these VMs are deployed as part of setting up the Supervisor Cluster, however I found a way to tell the Workload Control Plane (WCP) to only deploy two 🙂


This minimal deployment of vSphere with Kubernetes has already been incorporated into my vSphere with Kubernetes deployment script, but it does require altering several specific settings. You can find the instructions below.

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Configure log forwarding from Tanzu Kubernetes Grid (TKG) to vRealize Log Insight Cloud

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As much as I enjoy kubectl'ing logs in real time for troubleshooting and debugging purposes, this usually does not scale beyond a couple of Kubernetes (K8s) Clusters if you are lucky. Even then, you will not retain any of the historical logs which may be required for deeper analysis or for auditing purposes. This is usually solved by having a centralized log management platform and while working with Tanzu Kubernetes Grid (TKG) running on VMware Cloud on AWS, a solution like vRealize Log Insight Cloud (vRLIC) makes a lot of sense.

While browsing through the vRLIC console, I noticed that it supports a number of log sources including K8s which was exactly what I was looking for. However, after going through the instructions in configuring fluentd on my TKG Cluster, I found that that nothing was being sent. After a bit of debugging, I realized a few steps were actually missing that was required to setup this up on TKG Cluster.

I eventually figured it out and will be sharing this feedback with the vRLIC folks but in the meantime, you can follow the instructions below on how to forward both system and application logs from your TKG Cluster or any K8s deployment for that matter which has outbound connectivity to connect to vRLIC.


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