Learn Kubernetes Weekly issue 206 · 21 Oct 2026

DNS on AWS, ConfigMap Volume Delays, Command Injection: kubectl-mcp-tool, PostgreSQL on Harvester, Cutting Cassandra Costs

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Articles

1. DNS is weird inside Kubernetes on AWS

   dev.to

   This article explains three things that make DNS feel strange inside Kubernetes on AWS: the ndots setting, NodeLocal DNS caching, and a hidden per-ENI packet limit.

2. How to Eliminate Shared Production Kubeconfigs

   goteleport.com

   This tutorial explains why shared production kubeconfigs prevent per-user access revocation and shows how to replace reusable certificates and tokens with individual SSO logins, short-lived credentials, exec plugins, and RBAC.

   sponsored

3. TIL: Kubernetes ConfigMap Volume Mounts Are Eventually Consistent — Not Immediately Consistent

   chaitanyawaikar1993.medium.com

   This article explains why a ConfigMap you just changed via the API still appears outdated in the mounted file, and why the kubelet can take up to a minute to catch up.

4. CVE-2025-69902: OS Command Injection in kubectl-mcp-tool

   onemore-hayeon.github.io

   This write-up details CVE-2025-69902, a command-injection flaw in a kubectl MCP server that runs user input through a shell, letting an attacker execute arbitrary commands on the host.

5. Building the Foundation for PostgreSQL Lifecycle Management in a DBaaS on Harvester

   medium.com

   This case study shows how a PostgreSQL service on Harvester uses prebuilt VM images to start databases faster, save disk space, and handle OS updates and version end-of-life safely.

6. We Cut Our Cassandra Bill From $30K to $10K a Month by Self-Hosting on Kubernetes

   medium.com

   This case study shows how a team cut its Cassandra bill from $30K to $10K a month by running K8ssandra across four EKS regions and moving traffic with no downtime.

Articles worth checking out:

• How I Saved Azure Compute Costs by Automatically Shutting Down Our Dev Kubernetes Cluster Every Night

• Managing Hundreds of Kubernetes Overlays at Scale with Kustomize

Tutorials

1. SSO-Backed kubectl Access Across Many Clusters

   goteleport.com

   This tutorial explains how to secure SSO-backed kubectl access across development, staging, and production clusters by using separate OIDC audiences so cached tokens cannot authenticate to the wrong cluster.

   sponsored

2. Building a Production-Grade Apache Spark Platform on Kubernetes

   medium.com

   This tutorial shows how to run a multi-tenant Spark platform on Kubernetes with Spark Operator, Volcano, Helm, Airflow, shared images, workload limits, and monitoring.

3. Scaling Long-Running AI Agents: Async Workers on Kubernetes with LangGraph and KEDA

   medium.com

   This tutorial shows how to run long-running LangGraph agents as Kubernetes workers using SQS, save progress to PostgreSQL, and scale based on queue length with KEDA.

4. Distributed k6 Load Testing on Amazon EKS with Kubernetes Jobs and Dedicated Managed Node Groups

   medium.com

   This tutorial shows how to run distributed k6 load tests on Amazon EKS with Indexed Jobs, keep test workers on a separate node group, and check application and autoscaling limits.

5. Service Discovery and Service Mesh in .NET

   medium.com

   This tutorial shows you how to implement service discovery in .NET with Kubernetes DNS, Microsoft.Extensions.ServiceDiscovery, Consul, and Dapr while ordering resilience handlers correctly.

More tutorials:

• Building a Kubernetes Admission Controller: Automating Security Policy Enforcement

Kubernetes jobs

1. • DevOps Engineer with Raft Company Website

   • Salary: $120K to $210K a year

   • Location: remote from

   • Tech stack: Kubernetes, Kubernetes, AWS EC2, AWS, Azure, Docker, On-premise, Fluent Bit, OpenTelemetry, Kibana

2. • DevOps Engineer with Raft Company Website

   • Salary: $110K to $200K a year

   • Location: based in the office in Huntsville, AL, USA

   • Tech stack: Kubernetes, Kubernetes, OpenShift, CICD, AI/ML, Agentic AI, Cloud-Native, design thinking, cloud-native architectures, Complex Application Development

3. • DevSecOps Engineer with Raft Company Website

   • Salary: $140K to $160K a year

   • Location: remote from

   • Tech stack: Kubernetes, Kubernetes, on-premises, AWS, Cloud, Docker, Fluent Bit, Kibana, Loki, monitoring

4. • DevSecOps Engineer with Reltio

   • Salary: $145K to $207K a year

   • Location: remote from

   • Tech stack: Kubernetes, Kubernetes, AWS, Azure, GCP, ArgoCD, Jenkins, NeMo Guardrails, SOC 2, Cycode

5. • Account Executive, Commercial with Everpure

   • Salary: $0 to $517.18K a year

   • Location: remote from

   • Tech stack: Kubernetes, cloud computing, data platform, Storage, Kubernetes data services, AI ecosystem, AI hardware, AI

Discover more Kubernetes jobs on Kube Careers →

Code & tools

1. KubeDesk: Desktop Kubernetes Management Without kubectl

   github.com/ysrgozudeli

   KubeDesk is a cross-platform Kubernetes desktop app for browsing resources, viewing health and topology, streaming logs, opening shells, and making dry-run validated changes.

2. SnowOps Labs: Hands-On Kubernetes Failure Lab

   github.com/sagar2395

   SnowOps Labs is a Kubernetes practice lab that builds a local cluster, injects realistic failures, and grades your fixes through guided scenarios and incidents.

3. Diagnose Broken kubeconfigs with kubectl-config-doctor

   github.com/aptakube

   kubectl-config-doctor is a CLI plugin that detects broken, misconfigured, or unreachable kubeconfig setups—catching issues like duplicate contexts, invalid auth methods, missing files, or unreachable APIs.

4. Kubernetes-Native Orchestration for NVIDIA BlueField DPUs

   github.com/NVIDIA

   DPF is a Kubernetes-native framework for provisioning and orchestrating NVIDIA BlueField-3 DPUs.

   It abstracts DPU management and offloads networking and storage workloads from host servers to Linux-based arm64 DPUs using the DOCA software stack.

5. High-Performance NVMe-oF Storage for Kubernetes

   github.com/simplyblock-io

   If you're running I/O-intensive workloads, traditional block storage latency becomes a bottleneck.

   Simplyblock CSI bypasses kernel I/O and leverages user-space SPDK over NVMe-oF to deliver bare-metal performance within Kubernetes.

Upcoming Kubernetes events

1. Oct

   22

   Advanced Kubernetes course

   Online workshop organized by LearnKube.

   • This is a virtual event

   • This event requires an entrance fee

2. Oct

   24

   Kubernetes Community Days Nigeria 2026

   In-person conference organized by KCD Nigeria.

   • Location: Lagos, NG

   • This is a free event.

3. Oct

   27

   Cloud Native Days Norway

   In-person conference organized by CND Norway.

   • Location: Bergen, NO

   • This event requires an entrance fee

4. Oct

   28

   ContainerDays & AI Context Singapore

   In-person conference organized by ContainerDays.

   • Location: Singapore, SG

   • This event requires an entrance fee

5. Oct

   29

   Dutch Cloud Native Day

   In-person conference organized by Dutch CND.

   • Location: Utrecht, NL

   • This event requires an entrance fee

Discover more Kubernetes events on Kube Events →

Kubernetes call for papers

1. 33

   days

   Big Data Europe

   The Call For Paper is open until 23 November 2026 at UTC. More info →

   • Location: Vilnius, LT

   • In-person conference organized by DATA MINER.

   • The conference starts on the 27 November 2026.

   • Apply here

2. 11

   days

   Devopsdays Los Angeles

   The Call For Paper is open until 1 November 2026 at UTC. More info →

   • Location: Los Angeles, CA, USA

   • In-person conference organized by DevopsDays.

   • The conference starts on the 2 April 2027.

   • Apply here

3. 52

   days

   APE 2026

   The Call For Paper is open until 12 December 2026 at UTC. More info →

   • Location: Apenheul, NL

   • In-person conference organized by Stichting Meetups.

   • The conference starts on the 11 December 2026.

   • Apply here

4. 15

   days

   Open Source Conference Kolkata

   The Call For Paper is open until 5 November 2026 at UTC. More info →

   • Location: Kolkata, IN

   • In-person conference organized by Open Source Con India.

   • The conference starts on the 5 December 2026.

   • Apply here

5. 72

   days

   Devopsdays Raleigh

   The Call For Paper is open until 1 January 2027 at UTC. More info →

   • Location: Raleigh, NC, USA

   • In-person conference organized by Devopsdays.

   • The conference starts on the 27 April 2027.

   • Apply here

6. 11

   days

   AI Conf Asia

   The Call For Paper is open until 1 November 2026 at UTC. More info →

   • Location: Kathmandu, NP

   • In-person conference organized by wwktm.

   • The conference starts on the 8 January 2027.

   • Apply here

7. 1

   days

   Platform Engineering 2026

   The Call For Paper is open until 22 October 2026 at UTC. More info →

   • This is a virtual event

   • Online meetup organized by Conf42.

   • The meetup starts on the 5 November 2026.

   • Apply here

8. 10

   days

   Build It Summit

   The Call For Paper is open until 31 October 2026 at UTC. More info →

   • Location: Paris, FR

   • In-person conference organized by Build It Summit.

   • The conference starts on the 1 December 2026.

   • Apply here

9. 41

   days

   ContainerDays & AI Context London 2027

   The Call For Paper is open until 1 December 2026 at UTC. More info →

   • Location: London, GB

   • In-person conference organized by Dockland Media Group.

   • The conference starts on the 11 February 2027.

   • Apply here

Until next time!

— Gulcan