TKG

Tanzu Kubernetes Grid (TKG) Demo Appliance 1.2.1

01/05/2021 by William Lam 3 Comments

Check out the newest release of the Tanzu Kubernetes Grid (TKG) Demo Appliance Fling which includes the following new features:

Support for the latest TKG 1.2.1 release
Support for TKG Workload Cluster upgrade workflow from Kubernetes v1.18.10 to v1.19.3
Updated embedded Harbor to use self-sign TLS certificate

One of the biggest feature I was excited for in the new TKG 1.2.1 release was support for an external container registry that was configured with a self-signed TLS certificate. Previously, TKG only supported container registries that were configured with a trusted CA signed certificate and that made it difficult for proof of concept/testing but also for environments that were air-gapped.

With previous releases of the TKG Demo Appliance, a valid TLS certificate was acquired from Let's Encrypt (LE) with the help of my good friend Ryan Johnson who owns the domain rainpole.io. The one downside to LE-based certificates is the short expiry period, which is every 90 days. This meant that any TKG Demo Appliance deployed after the expiry would stop functioning due to the certificate no longer being valid. Although I have been able to manage this by updating the appliance roughly every 90 days, usually in-conjunction with new release of TKG, it was less than ideal.

Customizing Kubernetes cluster template (Dev/Prod) plans in Tanzu Kubernetes Grid 1.2

10/20/2020 by William Lam Leave a Comment

With previous releases of Tanzu Kubernetes Grid (TKG), if you needed to apply special OS customizations that were applied to the deployed Control Plane and Worker Node VMs, such as injecting commands to handle network proxy or dealing with insecure container registry, your only option was to hand edit the default TKG Dev/Prod YAML templates. Not only was this error prone but because the templates can change from each release, it was difficult to manage and test until you attempted a deployment.

One of the newest features with the release of TKG 1.2 is official support for customizing the Kubernetes (K8s) Cluster Templates Plans using YTT (YAML Templating Tooling) which allows users to provide custom data that can then be patched/overlay to an existing YAML file. YTT itself is part of a larger toolset for building, creating and configuring deployments for K8s called Carvel. The Domain Specific Language (DSL) that YTT uses was not exactly intuitive but since the official TKG documentation had an example to start with, I was able to mostly figure my way through along with some tips from the #carvel Slack channel.

So what was I trying to do? I was working on updating my TKG Demo Appliance Fling to the latest 1.2 release and part of the setup required adding an entry to /etc/hosts file on all TKG VMs that are deployed. Instead of directly messing with the YAML templates, there is now a new "overlay" YAML file in ~/.tkg/providers/infrastructure-vsphere/ytt/vsphere-overlay.yaml which can be used to make such changes.

Tanzu Kubernetes Grid (TKG) Demo Appliance 1.1.3

08/10/2020 by William Lam 1 Comment

It has been awhile since I have updated my Tanzu Kubernetes Grid (TKG) Demo Appliance Fling, which is a virtual appliance that enables anyone to go from zero to Kubernetes in less than 30 minutes with just an SSH client and a web browser. For VMware Cloud on AWS customers interested in running TKG, this is a great way to quickly get started on a proof of concept, demo or for development and testing purposes. One great benefit is that everything required for TKG is self contained within the appliance including an embedded Harbor registry and the respective TKG container images, great for air-gapped or non-internet accessible environments.

Here is a summary of what is new:

Support for latest TKG 1.1.3

There have been several of smaller releases to TKG since their 1.0.0 release but due to their short lifecycle, I decided to hold off. Behind the scenes, I have actually been working closely with TKG team on the latest TKG 1.1.3 release which was just release last week. One really cool feature that was introduced in TKG 1.1.2 is the ability to upgrade an existing TKG Workload Cluster to a newer version of Kubernetes.

With TKG 1.1.3, support for Kubernetes v1.18.6 and v1.17.9 is now possible and the latest version of the demo appliance will also support this workflow. In fact, I have also updated my TKG Workshop Guide to include all new updates including the upgrade workflow. To reduce the maintenance burden on myself, the TKG Demo Appliance 1.0.0 will be removed in the near future, for now it has been deprecated but all existing content is still available. I highly recommend checking out the latest version as you will get all the latest features of TKG.

Tanzu Kubernetes Grid (TKG) Demo Appliance for VMC and vSphere

05/11/2020 by William Lam 8 Comments

As some of you can probably tell from my recent Twitter updates and blog posts (here and here) that I have been spending some time lately with both vSphere with Kubernetes and Tanzu Kubernetes Grid (TKG). Like many of you in the community, I am still pretty new to Kubernetes (K8s) and I am still learning about what it has to offer both from an infrastructure standpoint but more importantly how it can be used to deliver new and modern applications. I am also very lucky to be part of the the VMware Event Broker Appliance Open Source Fling project which builds and runs on top K8s and this project has allowed me to really get hands on which is how I learn best.

A couple of months back I was asked to put together a workshop to demonstrate how to deploy TKG Clusters running on VMware Cloud on AWS (VMC) and while developing the workshop, I thought it would be really cool if I could make it even easier for anyone that is brand new to K8s to quickly get started with TKG. I wanted to have a solution that can literally be dropped into any supported vSphere-based environment with basic networking to go from Zero to Kubernetes in less than 30 minutes!

Enter the Demo Appliance for Tanzu Kubernetes Grid (TKG) Fling

A Virtual Appliance that pre-bundles all required dependencies to help customers in learning and deploying standalone Tanzu Kubernetes Grid (TKG) clusters running on either VMware Cloud on AWS and/or vSphere 6.7 Update 3 environment for Proof of Concept, Demo and Dev/Test purposes. This appliance will enable you to quickly go from zero to Kubernetes in less than 30 minutes with just an SSH client and a web browser!

In addition to the appliance, I have also put together a step by step workshop-style guide which not only walks you through in deploying your first TKG Cluster but also provide some example demos and references which you can explore further. Below are some of the highlights of the Demo Appliance for TKG:

Configure non-secure Harbor registry with Tanzu Kubernetes Grid (TKG)

05/09/2020 by William Lam 3 Comments

In an earlier blog post, I shared the steps to to configure Harbor with a proper signed SSL certificate that would serve as private container registry for Tanzu Kubernetes Grid (TKG) CLI running in an air-gapped environment.

Although Harbor can easily be configured to support custom CA signed certificate, self-sign certificate and even just using HTTP, there are several additional steps and dependencies that is required if you wish to use a non-secure container registry with TKG CLI. This definitely was a bunch of trial/error and hopefully this can be made easier in the future to easily enable non-secure registry support with TKG CLI out of the box for development and testing purpose.

I also want to give a huge thanks to Jun Wang from our Modern Application Business Unit (MAPU), he was instrumental in helping me out and ultimately his tip on updating the containerd configuration was the last piece to the puzzle so that the K8s images deployed would use our insecure Harbor registry for pulling container images.

Deploy Harbor in an Air-Gapped environment for Tanzu Kubernetes Grid (TKG)

04/24/2020 by William Lam 1 Comment

When using Tanzu Kubernetes Grid (TKG) and the new TKG CLI, outbound internet connectivity is required as part of the initial setup on the machine running TKG CLI but also on the TKG Management Cluster which is automatically stood up as part of the deployment. For demo and testing purposes, this is usually not a problem but for anyone looking to run this in a Production or datacenter environment, direct internet access is generally not available.

TKG does support air-gapped environments today by requiring a private container registry that has been configured with all the required containers. Once your registry has been setup, you will also need to update the TKG YAML manifest files to specify your private registry as by default, it will point to registry.tkg.vmware.run. You can use any container registry that is supported with Kubernetes including the popular Harbor solution. One thing to note is that your private registry must have a proper signed SSL certificate, custom CA certificates or self-signed certificates are not officially supported today with TKG.

Since I recently had to set this up for a project I am working on, which I hope to talk about in a future blog post, I thought it would be useful to share the instructions on how to setup and configure Harbor to be used in-conjunction with TKG as well as any other solution that requires a container registry running in your own environment. In my deployment, I will be using Let's Encrypt for generating the required SSL certificate, but you can use any existing service for performing this operation. I will also be installing Harbor on Photon OS, but you can use any operating system of your choice that Harbor is supported on.

Pre-Requisites

Access to a public DNS domain which you have ownership of (e.g. adding new records)
Access to your internal DNS server to add a custom DNS zone lookup entry (e.g. registry.<yourdomain>.com)