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🐝 About SketchOps

Welcome to SketchOps.

SketchOps is a personal blog where I document things I learn, build, troubleshoot, and explore.

This site contains notes, tutorials, technical guides, engineering insights, lessons learned, and useful references collected along the way.

Topics may include technology, software engineering, cloud computing, automation, DevOps, AI, productivity, and other subjects that spark curiosity.

The purpose of this blog is simple:

  • Learn continuously
  • Document useful knowledge
  • Share ideas and experiences
  • Help others solve problems faster

Whether you're here to learn something new, troubleshoot an issue, or simply explore interesting topics, I hope you find something useful.

Thanks for visiting SketchOps.

🐝 Keep learning. Keep building.

Popular posts from this blog

☁️ AWS Global Accelerator (GA) + Route 53

🟧☁️ AWS + 🌍 Global Accelerator (GA) + 🌐 Route 53 what they are and how they work together (especially for ALB/EKS). ☁️ AWS = Cloud platform 🌍 GA = Fast global routing + static IPs 🌐 Route 53 = DNS ☁️ What is AWS? AWS (Amazon Web Services) is Amazon’s cloud platform where you run servers, containers, databases, networking, DNS, monitoring, and more. EC2 (servers), EKS (Kubernetes), RDS (databases) ALB/NLB (load balancers), S3 (storage), Route 53 (DNS) What is AWS Global Accelerator? Global Accelerator (GA) improves availability and performance by routing users through AWS’s private global network to the nearest healthy endpoint . Key idea: Users hit GA (static Anycast IPs). GA picks the best Region/endpoint automatically. Static Anycast IPs (2 fixed IP addresse...
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🐳 Docker Filesystem Internals (AdvancEd)

Docker Filesystem Internals (Advanced) This post is for readers who already understand Docker basics and want to learn how Docker manages files internally. If you are new to Docker, read the beginner guide first. Containers Do NOT Have Their Own Disk A common misunderstanding is that Docker containers have their own disk. In reality: Containers do not have a separate physical filesystem. Docker creates a filesystem view using layers stored on the host machine. This layered filesystem is implemented using a Union Filesystem , most commonly OverlayFS on Linux. Docker Images Are Read-Only Layers A Docker image is made up of multiple read-only layers. Each instruction in a Dockerfile creates a new layer. FROM python:3.11 RUN pip install flask COPY app.py . This results in layers lik...
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Understanding RabbitMQ Classic Mirrored Queues and Quorum Queues

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💚💚 💚 Understanding RabbitMQ Classic Mirrored Queues and Quorum  Queues 💚💚 💚   I understood RabbitMQ only after I understood why Classic Mirrored Queues were replaced . When I first started learning RabbitMQ, I kept hearing: Classic Queues Classic Mirrored Queues Quorum Queues Raft Consensus Everyone said:  "Use Quorum Queues." But I couldn't understand why. To understand Quorum Queues , I first had to understand how Classic Mirrored Queues worked.
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🐳 Docker Tutorial for Beginners: Step-by-Step with a Simple Example

Docker Explained Using a Very Simple App (Beginner Friendly) Goal: Build a tiny Python app, run it normally, then run the same app using Docker, and understand why Docker helps. Step 1: Create a Very Small Python App Create a file named app.py : print("Hello I am running inside Docker!") Step 2: Run the App WITHOUT Docker Run this on your machine: python app.py Common real-life problems: Python not installed, wrong Python version, missing dependencies, different OS behavior this is where the “works on my machine” issue starts. Step 3: Introduce Docker Instead of relying on your system, Docker lets you package the runtime (Python) together with your app. We’ll do that using a Dockerfile . Step 4: Create a Dockerfile Create a file named Dockerfile (no extension): FROM python:3.11 WORKDIR /app COPY app.py . CMD ["py...
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☸️What’s Inside EKS? A Beginner’s Guide to Its Core Components

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 EKS (Elastic Kubernetes Service) EKS is a managed service by AWS that runs Kubernetes for you. It takes care of setting up and managing the Kubernetes control plane so you can focus on running your applications. Kubernetes  Kubernetes is an open-source system for automating the deployment, scaling, and management of containerized applications. It helps run apps reliably across a cluster of machines, automatically handling scheduling, scaling, updates, and recovery. Pod A Pod is the smallest unit in Kubernetes. It can hold one or more containers that share the same network and storage. All containers in a pod are scheduled and managed together. Container A Container is a lightweight, standalone package that includes everything an app needs to run — code, runtime, libraries, and dependencies. It ensures the app runs the same no matter where it’s deployed. 👀1 pod can have multiple containers but 1 container cannot belongs to multiple pods.
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☸️ Kubernetes Taints and Tolerations(with Node Affinity)

Kubernetes Taints and Tolerations(with Node Affinity + EKS Upgrade Context) Kubernetes scheduling is the process of deciding which node runs a given Pod . This page explains how Kubernetes keeps Pods away from “inappropriate” nodes using taints (node-side restrictions) and tolerations (pod-side permissions), and how that relates to node affinity (pod-side attraction). 1) Core idea: attraction vs repulsion Node affinity (attraction) Node affinity is a property of Pods that attracts them to a set of nodes. You can express it as: Hard requirement (must match), or Preference (nice to have). Taints (repulsion) Taints are the opposite of node affinity. They allow a node to repel a set of Pods. Tolerations (permission) Tolerations are applied to Pods. A toleration allows the scheduler to schedule Pods onto nodes with matching taints. Important...
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AWS Load Balancer Controller Upgrade Guide: v2.x to v3.3

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AWS Load Balancer Controller Upgrade Guide: v2.x to v3.3 What is AWS Load Balancer Controller? AWS Load Balancer Controller is a Kubernetes controller that integrates Amazon EKS with AWS Elastic Load Balancing services. It watches Kubernetes resources and automatically creates or updates AWS load balancing resources based on the desired state defined inside the cluster. Instead of manually creating load balancers, listeners, target groups, and security group rules in AWS, teams can define Kubernetes resources such as Ingresses and Services. The controller then reconciles those resources with AWS. What Does It Manage? AWS Load Balancer Controller commonly manages: Application Load Balancers (ALB) Network Load Balancers (NLB) Listeners and listener rules Target groups Target registration and deregistration Security group rules Ingress resources TargetGroupBinding resources Beca...
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🐳 Build a Tiny Flask Web App in Docker (with Ports)

docker run -p 8080:5000 flask-hello Then open in your browser: http://localhost:8080 Step 6: Stop the container Press Ctrl + C in the terminal. Quick Troubleshooting Browser says “This site can’t be reached”: Make sure the container is running and you used the -p port mapping. Flask runs but not accessible: Confirm Flask is running with host="0.0.0.0" inside Docker (not 127.0.0.1 ). Port already in use: Try using a different host port, for example: docker run -p 9090:5000 flask-hello Next Post Ideas Docker image layers and caching (explained simply) Docker volumes : keeping data after a container stops Running the same container in Kubernetes (Pod basics)
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☁️ Amazon S3 Explained: More Than Just Object Storage

Amazon S3 Explained: More Than Just Object Storage When people hear Amazon S3 , they usually think it is only used to store files like images, logs, backups, or documents. That is true, but S3 has grown into much more than simple object storage. Today, S3 can be used for object storage, file-like access, immutable backups, lifecycle management, static websites, event-driven workflows, analytics, and data lake storage. In this post, let us understand what S3 is and how it is used in real-world AWS environments. 1. What is Amazon S3? Amazon S3 stands for Simple Storage Service . It is mainly an object storage service . In S3, data is stored as objects inside buckets. Bucket → Object Each object usually contains: The actual data Metadata A unique object key Example: Bucket name: my-app-logs Object key: logs/2026/app.log Even though this looks like a folder path, S3 does not work like a traditional filesystem internally. The folder-like str...
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☸️ CoreDNS and AWS VPC CNI in EKS

CoreDNS vs AWS VPC CNI in EKS: What Each Component Actually Does When working with Amazon EKS , two important components help your Kubernetes cluster communicate properly: CoreDNS and AWS VPC CNI . Both are part of the networking story, but they do very different jobs. CoreDNS helps pods find services by name, while AWS VPC CNI gives pods network connectivity using IP addresses from your AWS VPC. In simple words: CoreDNS answers: “What IP address belongs to this service name?” AWS VPC CNI answers: “How does traffic reach that pod over the network?” 1. What is CoreDNS? CoreDNS is the DNS server used inside Kubernetes. Its main job is to resolve Kubernetes service names into IP addresses. For example, if one pod wants to call another service using a name like: user-service.default.svc.cluster.local CoreDNS resolves that service name into the correct Kubernetes service IP. What CoreDNS Does Resolves Kubernetes service names Supports pod-to...
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