Learn Kubernetes Weekly issue 53

Choosing a worker node size, Bolstering security & automating EKS clusters, Scaling Rails with HPA, Bypassing admission webhooks, resize CPU limits

15 Nov 2023

Articles

1. Architecting Kubernetes clusters — choosing a worker node size

   Daniele Polencic

   What type of worker nodes should you use for your Kubernetes cluster?

   And how many of them?

   This article looks at the pros and cons.

2. Bolstering security & automating management of Target Australia's EKS clusters

   Gazal Gafoor

   This article covers the lesson learned at Target Australia from running EKS at scale:

   1. The usage of Bottlerocket and its security benefits
   2. How Karpenter is a more cost-effective and flexible solution than the Cluster Autoscaler.

3. Automatically scale your rails application with HPA

   Luca Mattivi

   In this case study, you'll learn how the team at Treatwell customised metrics for the Horizontal Pod Autoscaler, optimising the system's response to varying traffic demands and reducing their monthly costs by 35–40%.

4. How to bypass admission webhooks and have a giant security hole

   Kostiantyn Skraga

   In this article, you'll discuss the security risks associated with the deprecation of Pod Security Policies and potential issues with webhook validation that could lead to a compromised cluster.

5. Unleashing the power of Kubernetes: deploying containers with cluster resource access

   Franco Stellari

   In this article, you'll learn how to use Cluster Role, Cluster Role Binding, and Service Account to deploy a simple application capable of accessing the cluster's resources using kubectl from within a pod.

6. Validate if Kubernetes deployments have LivenessProbe and ReadinessProbes

   Ivan Herrmann Cini

   In this tutorial, you will learn how to write a validating admission controller to check if Deployments have the proper liveness and readiness probes in place.

Articles worth checking out:

• Pods and WorkerNodes  —  control the placement of the Pods on the Nodes

• Leveraging on-demand/spot ratio split technique for splitting a workload across on-demand and spot instances in a desired ratio

• Beta support for using swap on Linux

• Raft: understandable distributed consensus

• Autoscaling in Kubernetes: understanding Vertical Pod Autoscaler

• We save thousands every month by using incremental snapshots with our Velero backups

• ArgoCD: multi-tenancy strategy

• Platform engineering: learning from the Kubernetes API

• Semantic versioning with Helm and GitHub Actions

• Troubleshooting kube-proxy and RKE2-Canal pods restart loop: lessons from upgrading Ubuntu 20.04

• OpenAI-based open source tools for Kubernetes AIOps

Tutorials

1. Resize CPU limit to speed up Java startup on Kubernetes

   Piotr Minkowski

   In this article, you'll learn how to solve the slow startup times of Java apps on Kubernetes related to CPU limit.

   You'll use the In-place Pod Vertical Scaling feature to resize resources (CPU or memory) assigned to the containers without restarting.

2. Pod restart notifier operator CRD

   Nikos Nikolakakis

   In this guide, you'll learn how to create a Kubernetes operator called pod-restart-notifier with kubebuilder.

   The operator uses Custom Resource Definitions to define custom resources and manage their lifecycle.

3. Vault: externals secrets in Kubernetes cluster

   Clement Verove

   In this tutorial, you will learn how to store your sensitive secrets in a self-hosted Vault and share them with a Kubernetes cluster.

4. How to list Kubernetes pods using the Go SDK

   Faizan Bashir

   This article will walk you through listing Pods and Namespaces in a Kubernetes cluster with the help of go-client SDK.

Kubernetes jobs

1. • Machine Learning Engineer with FATHOM

   • Salary: $160K to $220K a year

   • Location: remote from the United States

   • Tech stack: Kubernetes, AWS, Airflow

2. • DevSecOps Engineer with Angi

   • Salary: $175K to $185K a year

   • Location: remote from the United States

   • Tech stack: Kubernetes, AWS, On-premise, Helm, Python, SQL, Java, Scala, Ruby, Terraform

3. • Platform Engineer with Altos Labs

   • Salary: $153K to $273.7K a year

   • Location: based in the office in San Diego, CA, USA

   • Tech stack: Kubernetes, AWS, On-premise, Docker, Shell, Python, Terraform, CDK, Ansible, Grafana

Discover more Kubernetes jobs on Kube Careers →

Code & tools

1. kpack: Kubernetes-native container build service

   kpack extends Kubernetes and utilizes unprivileged kubernetes primitives to provide builds of OCI images as a platform implementation of Cloud Native Buildpacks (CNB).

2. Koordinator: QoS-based scheduling

   Koordinator is a QoS-based scheduling system for hybrid orchestration workloads on Kubernetes.

   Its goal is to improve the runtime efficiency and reliability of both latency-sensitive workloads and batch jobs.

3. AWS Load Balancer Controller

   AWS Load Balancer Controller is a controller to help manage Elastic Load Balancers for a Kubernetes cluster.

   It satisfies:

   • Ingress resources by provisioning Application Load Balancers.
   • Service resources by provisioning Network Load Balancers.

4. KubeBlocks: manage database workloads

   KubeBlocks is an open-source Kubernetes operator that manages relational, NoSQL, vector, and streaming databases on the public cloud or on-premise.

   It is designed for production, providing reliable, performant, cost-effective data infrastructure.

5. Claudie: managing multi-cloud and hybrid-cloud

   Claudie is a platform for managing multi-cloud Kubernetes clusters with each node pools in a different cloud provider.

Other interesting projects:

• Liqo: multi-cluster topologies

• KubeLinter

Upcoming Kubernetes events

1. Nov

   17

   Getting started with containers and Kubernetes

   Online workshop organized by #thenewITgirls.

   • This is a virtual event

   • This is a free event.

2. Nov

   15

   DeveloperWeek Enterprise 2023

   Online conference organized by DevNetwork.

   • This is a virtual event

   • This event requires an entrance fee

3. Nov

   16

   Certified Kubernetes administrator hands-on

   Online workshop organized by Cloud Native Islamabad.

   • This is a virtual event

   • This is a free event.

4. Nov

   18

   Helm 101: mastering Kubernetes application management with Helm

   Online meetup organized by Women in Cloud Native.

   • This is a virtual event

   • This is a free event.

5. Nov

   22

   Harnessing the power of operators in Kubernetes

   Online & in-person meetup organized by Cloud Native Vienna.

   • Location: Vienna, AT and virtual

   • This is a free event.

Discover more Kubernetes events on Kube Events →

Kubernetes Call for Papers

1. expired

   KubeCon + CloudNativeCon Europe

   The Call For Paper was open until 26 November 2023 at UTC. More info →

   • Location: Paris, FR

   • In-person conference organized by Linux Foundation.

   • The conference starts on the 19 March 2024.

   • Apply here

2. expired

   Kubernetes Community Days Kerala 2024

   The Call For Paper was open until 18 November 2023 at UTC. More info →

   • Location: Kochi, IN

   • In-person conference organized by KCD Kerala.

   • The conference starts on the 3 February 2024.

   • Apply here

3. expired

   Kubernetes Community Days Costa Rica 2024

   The Call For Paper was open until 1 February 2024 at UTC. More info →

   • Location: Heredia, CR

   • In-person conference organized by KCD Costa Rica.

   • The conference starts on the 1 March 2024.

   • Apply here

4. expired

   One Summit

   The Call For Paper was open until 4 December 2023 at UTC. More info →

   • Location: San Jose, CA, USA

   • In-person conference organized by Linux Foundation.

   • The conference starts on the 29 April 2024.

   • Apply here

5. expired

   Devopsdays Birmingham (AL)

   The Call For Paper was open until 1 December 2023 at UTC. More info →

   • Location: Birmingham, AL, USA

   • In-person conference organized by Devopsdays.

   • The conference starts on the 18 April 2024.

   • Apply here

6. expired

   Devdays Europe

   The Call For Paper was open until 31 January 2024 at UTC. More info →

   • Location: Vilnius, LT and virtual

   • Online & in-person conference organized by DATA MINER.

   • The conference starts on the 20 May 2024.

   • Apply here

7. expired

   Devopsdays Istanbul

   The Call For Paper was open until 23 January 2024 at UTC. More info →

   • Location: Istanbul, TR

   • In-person conference organized by Devopsdays.

   • The conference starts on the 20 April 2024.

   • Apply here

8. expired

   Devopsdays Raleigh

   The Call For Paper was open until 27 January 2024 at UTC. More info →

   • Location: Raleigh, NC, USA

   • In-person conference organized by Devopsdays.

   • The conference starts on the 10 April 2024.

   • Apply here

9. expired

   DevSum 2024

   The Call For Paper was open until 3 December 2023 at UTC. More info →

   • Location: Stockholm, SE

   • In-person conference organized by Cornerstone.

   • The conference starts on the 15 May 2024.

   • Apply here

Until next time!

— Dan

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