Tag Archives: Kubernetes

MongoDB + Kubernetes Header

MongoDB Container data loss issue – A Journey

Over the past month or so I noticed an issue with my Pac-Man Kubernetes application, which I use for demonstrations as a basic app front-end that writes to a database back end, running in Kubernetes.

  • When I restored my instances using Kasten, my Pac-Man high scores were missing.
  • This issue happened when I made some changes to my deployment files to configure authentication to the MongoDB using environment variables in my deployment file.

This blog post is a detail walk-through of the steps I took to troubleshoot the issue, and then rectify it!

Summary if you don’t want to read the post

If you are not looking to read through this blog post, here is the summary:

  • I changed MongoDB images, I needed to configure a new mount point location to match the MongoDB configuration
  • New MongoDB image is non-root, so had to use an Init container to configure the permissions on the PV first
Overview of the application

The application is made up of the following components:

  • Namespace
  • Deployment
    • MongoDB Pod
      • DB Authentication configured
      • Attached to a PVC
    • Pac-Man Pod
      • Nodejs web front end that connects back to the MongoDB Pod by looking for the Pod DNS address internally.
  • RBAC Configuration for Pod Security and Service Account
  • Secret which holds the data for the MongoDB Usernames and Passwords to be configured
  • Service
    • Type: LoadBalancer
      • Used to balance traffic to the Pac-Man Pods

Pac-Man Kubernetes Diagram

Confirming the behaviour

The behaviour I was seeing when my application was deployed:

  • Pac-Man web page – I could save a high score, and it would show in the high scores list
    • This showed the connectivity to the database was working, as the app would hang if it could not write to the database.
  • I would protect my application using Kasten. When I deleted the namespace, and restored everything, my application would be running, but there was no high scores to show.
  • This was apparent from deploying the branch version v0.5.0 and v0.5.1 from my GitHub.
  • Deploying the branch v0.2.0 would not product the same behaviour
    • This configuration did not have any database authentication setup, meaning MongoDB was open to the world if they could connect without a UN/Password.
Testing the Behaviour

Continue reading MongoDB Container data loss issue – A Journey

Tanzu Blog Logo Header

VMUG Recording – Understanding Data Protection for your VMware Tanzu Container Workloads

As part of my virtual VMUG tour, I submitted a session to the VMUG call for papers covering the subject of Data Protection for Tanzu Kubernetes workloads. (Most of this will apply for any Kubernetes environments).

This was picked up by Erik at the Belgium VMUG for their UserCon in June 2021. After the session the videos remain available on demand for a short time, but there were no plans to upload this for everyone. So thank you to Michael Cade, whom offered to host this session for all on the Cloud Native Data ManagementYouTube Channel.

In the below session I cover the following areas;

  • ​What kind of data protection do you need?
  • ​Velero
    • The open source data protection project from VMware
  • ​Tanzu Mission Control
    • The Kubernetes fleet management platform that utilizes Velero from VMware.
  • ​3rd Party Options
    • A nod to the 3rd party ecosystem that offer enterprise Data Protection and Management software such as;
      • Kasten
      • PortWorx

There is even a quick technical demo in there, with a little technical hiccup I had to style out!



Recording – Kubernetes 101 – Getting started in the cloud native world

I had the pleasure of presenting this Kubernetes 101 session to the Veeam Community thanks to my work as part of their Veeam Vanguards program, and a special thank you to Michael Cade who co-presented with me!

In this session we cover the following with technical details included:

  • How have we got here?
  • Kubernetes – The Building Blocks
  • Policies
  • Wrap-up


VMware Tanzu Header

Deploying Tanzu Kubernetes Grid to AWS fails with ‘InstanceProvisionFailed’

The issue

When deploying Tanzu Kubernetes Grid to AWS, the deployment was failing with the following output:

unable to set up management cluster, : unable to wait for cluster and get the cluster kubeconfig: error waiting for cluster to be provisioned (this may take a few minutes): cluster creation failed, reason:'InstanceProvisionFailed @ Machine/tkg-aws-mgmt-control-plane-dqb4v', message:'1 of 2 completed'
The Cause

When we reviewed the CAPA logs (Cluster API AWS provider) we found the following errors logged: Continue reading Deploying Tanzu Kubernetes Grid to AWS fails with ‘InstanceProvisionFailed’

VMware Tanzu Header

Understanding the VMware Tanzu Kubernetes Terminology

It’s not uncommon for me to see the question asking for an explanation of VMware Tanzu Kubernetes terminology and differences between similar named products. As per the below tweet. This is my blog post to address the Tanzu Kubernetes terminology and use.

Twitter thread asking about TKGm and TKGs

First, we’ll break down the high level names and products. Then move into Tanzu Kubernetes products.

What is VMware Tanzu?

VMware Tanzu is a brand name covering VMware’s modern applications suite of products, just like vRealize is the suite name for VMware’s cloud management products.

What products are covered by the VMware Tanzu brand?

Continue reading Understanding the VMware Tanzu Kubernetes Terminology