William Lam

How to deploy Knative to a Tanzu Kubernetes Grid (TKG) Cluster on both vSphere with Tanzu and TKG Multi-Cloud?

11/23/2020 by William Lam Leave a Comment

This weekend I spent some time installing Knative, which is an open source framework that is built on top of Kubernetes. Knative is actually made up of two core components, serving and eventing. This quote from Ram Gopinathan, Principal Technology Architect, T-Mobile really sums up Knative quite nicely:

Knative helps our developers focus on building the business logic rather than worrying about building low-level platform capabilities such as build, deploy, autoscaling, monitoring, and observability.

There are a number of tutorials online for setting up Knative, most of which using Kubernetes in Docker (KinD) for easy local development. Since I have been spending quite a bit of time lately with both our vSphere with Tanzu and Tanzu Kubernetes Grid (TKG) Multi-Cloud solution, which both support deploying conformant and production grade Kubernetes (K8s) Clusters called a TKG Guest Cluster, I figure I might as well learn how to install Knative using these infrastructures.

The instructions below will be focus on deploying the Knative serving components. Once you have that setup, it is easy to deploy the eventing components which you can follow the official Knative documentation.

Quick Tip – Easily identify source DHCP server using ESXi DCUI

11/20/2020 by William Lam Leave a Comment

While installing the ESXi 7.0 Update 1 on one of my physical system, I happened to be in the "Configure Management Network" section of the ESXi Direct Console UI (DCUI) and noticed something I had never seen before. As shown in the screenshot, it now shows the IP Address of the DHCP server in which ESXi received the DHCP lease.

I had not noticed this before and after asking on Twitter, it looks like this is definitely a new enhancement that was added fairly recently. I did not see this in one of my ESXi 6.7 Update 3 deployments, but it may have came in a later patch but definitely new in ESXi 7.0 or greater. Not only is this a quick and easy way to identify the DHCP server being used but in case you need to track down an unexpected rogue DHCP server running, this will certainly come in handy as pointed out by John.

Trying to get rogue DHCP servers under control?
Remember kids, DHCP Snooping saves lives! https://t.co/FKPgKzI9In

— John Nicholson (@Lost_Signal) November 20, 2020

Why am I seeing HTTP communication status 404 error when configuring vSphere with Tanzu & how to fix?

11/16/2020 by William Lam 5 Comments

One thing I love about the VMware Community is the constant sharing of knowledge and information on a regular basis. I always enjoy discovering new tricks and tidbits from the community, especially as it helps me refine my own knowledge and understanding of a given technology or solution.

My good buddy Ariel Sanchez cc'ed me on Twitter yesterday referencing a blog post by Paul Wilk about an issue he was observing in his Nested ESXi environment when configuring vSphere with Tanzu.

This is interesting! Wonder if @lamw ir @eric_shanks have ever seen something like it

— Ariel Sanchez Mora (@arielsanchezmor) November 15, 2020

This was in regards to the dreaded 404 message displayed in the vSphere UI:

HTTP communication could not be completed with status 404

which is actually not unique to a Nested environment. In fact, this cryptic error message was observed even in the first release of vSphere with Tanzu which used to be called vSphere with Kubernetes with the release of vSphere 7.0 release.

Although Paul's conclusion on why his fixed work was not exactly correct, it was the fix itself that I was actually most interested in. Even with the initial vSphere 7.0 release, I had assumed this was just a cosmetic vCenter Server error message. It was not ideal, but like many other customers, I just ignored it as the enablement of Workload Management was still successful.

What helped me connect the dots was the fact that Paul solved the problem by disabling the ESXi firewall, which meant this was actually an ESXi issue. Given this was related to the OVF deployment, I immediately knew what this was actually referring to and is related to an earlier blog post I had shared about a new feature that would allow ESXi to "pull" remote OVF/OVA files from a HTTP(s) endpoint. In this case, it was not OVFTool driving the deployment but rather vCenter Server and the Content Library service, which is also responsible for OVF/OVA deployments.

It turns out that as part of deploying the Supervisor VMs, instead of using the typical "push" method for uploading an OVA, vCenter is instructing the ESXi host to "pull" the OVA files remotely which are actually hosted on the vCenter Server Appliance (VCSA) itself. What ends up happening is that because ESXi does not have the correct port in which the OVA is hosted on the VCSA, the "pull" method fails and it automatically falls back to the old "push" method. This is why you see the error message and then progress is immediately progressing.

How to build a customizable Raspberry Pi OS Virtual Appliance (OVA)?

11/16/2020 by William Lam Leave a Comment

After posting the instructions on how to install Raspberry Pi (rPI) OS into a Virtual Machine running on ESXi-Arm, I was already thinking about an easier consumption method that not only benefited VMware customers interested in running rPI OS as a VM but also the larger rPI OS development community. Just imagine, you can now easily deploy, build and test multiple rPI OS/application on a single physical rPI and get all the benefits of vSphere that many customers have enjoyed for the past two decades.

My goal was to build an rPI OS OVA that would enable some basic guest customization such as networking and configuring the password for the default pi user. As you can see from the screenshot below, I was able to accomplish this with minimal trial/error and works fantastic!

I was initially planning to release the rPI OS OVA as a VMware Fling which can then be made available to the community. However, due challenges in the way rPI OS is distributed today via an image file and the inclusion of packages that makes it difficult for redistribution, I decided to forgo the VMware Fling route and simply publish the instructions with some supplemental scripts that can be used to produce the same rPI OS OVA that I have built for my own personal use.

It would have been great if this could be made available and if anyone from Raspberry Pi organization is reading this and is interested in hosting the download, I would be more than welcome to provide you with OVA file.

Quick Tip – How to use Apple Thunderbolt 2 ethernet adapter with ESXi 7.0 or greater

11/13/2020 by William Lam Leave a Comment

I was doing some testing on my Apple 2018 Mac Mini with the latest ESXi 7.0 Update 1 release and I needed to setup a separate network connection as the onboard 10GbE was not working for me initially. I was out of ideas but I did remember that I still have my Apple Thunderbolt 2 to gigabit ethernet adapter which was something I had used quite a bit in the early days when I was using the Apple Mac Mini as my homelab system.

Like all recent Apple Mac's, the 2018 Mac Mini only supports Thunderbolt 3 (USB-C) ports and obviously not compatibility with the network adapter. Luckily, I did have an official Apple Thunderbolt 3 to Thunderbolt 2 adapter lying around which would allow me to connect the network adapter to the Mac Mini and to my surprise, it was automatically detected by the latest release of ESXi!

This partially came in a surprise because the Apple network adapter uses the Broadcom tg3 driver and I was not 100% sure if the native Broadcom (ntg3) would automatically claim this device since it was never officially supported.

Its definitely good to know this ethernet adapter still works as long as you have a TB2 to TB3 converter adapter and this should also work for any Intel NUC that have Thunderbolt 3 ports.

Automating kubectl-vsphere login for vSphere with Tanzu

11/12/2020 by William Lam 2 Comments

Before you can start deploying workloads to your vSphere with Tanzu Cluster, you need to first download the vSphere Plugin for Kubectl and then use that to login to your Supervisor Cluster which will generate a Kubernetes (K8s) context file that is stored in .kube/config

Here is an example of using the vSphere Plugin for Kubectl:

./kubectl-vsphere login --server=10.10.0.64 -u *protected email* --insecure-skip-tls-verify

For interactive sessions this is fine and upon successfully entering your password when prompted, you can switch to the correct K8s context to begin your workload deployment. For folks interested in automation, the one downside today is that the plugin does not provide a way to specify your password using either a command-line argument or reading from a configuration file.

I have actually seen this topic come up a few times both internally and externally for those wanting to automate the end to end deployment of a Tanzu Kubernetes Grid (TKG) Cluster and have gotten stuck on trying to figure a way around having to perform this required manual step.