What Is Blue-Green Deployment? A Plain English Explanation
Blue-green deployment explained simply — what it is, how it works, when to use it, and how it compares to canary deployments. With real Kubernetes examples.
129 articles
Blue-green deployment explained simply — what it is, how it works, when to use it, and how it compares to canary deployments. With real Kubernetes examples.
Learn Linux process signals every DevOps engineer must know: SIGTERM, SIGKILL, SIGHUP, SIGINT. How kill and pkill work, why Kubernetes uses SIGTERM, and how to handle signals in your app.
Kubernetes Endpoints and EndpointSlices explained from scratch — how Services use them to route traffic to pods, why empty Endpoints means no traffic reaches your app, and how to debug selector mismatches.
Learn what OCI (Open Container Initiative) is, what it standardizes, and why it matters for DevOps engineers. Covers image format, runtime spec, distribution spec, and practical tools like skopeo.
Learn what systemd is, how Linux services work, key systemctl commands, how to create a custom service, and how to read logs with journalctl — practical guide for DevOps engineers.
Learn what Docker multi-stage builds are and why they matter. Includes real examples shrinking a Go app from 800MB to 15MB and a Node.js app from 600MB to 80MB.
Learn Kubernetes pod affinity and anti-affinity with clear examples — required vs preferred rules, topologyKey, spreading replicas across zones, and co-locating pods for performance.
CSI (Container Storage Interface) drivers explained for beginners. Why they replaced in-tree plugins, how the controller and node plugin work, common CSI drivers, and how PVCs use them.
Learn Linux file permissions from scratch — how to read ls -la output, use chmod and chown, understand octal vs symbolic mode, SUID/SGID/sticky bit, umask, and why chmod 777 is dangerous.
TCP/IP is the foundation of all internet communication. Here's a clear explanation of the layers, protocols, and why they matter for debugging network issues in DevOps.
Docker and Kubernetes containers are built on Linux cgroups and namespaces. Understanding these fundamentals helps you debug container issues and set resource limits properly.
Rate limiting protects your APIs and infrastructure from overload and abuse. Here's what it is, how it works, and how to implement it in Nginx, Kubernetes, and code.
Processes, threads, PIDs, and signals — these come up constantly in DevOps work. Here's a clear explanation with real examples you'll actually use.
Init containers run before your main app container starts. Here's what they are, when to use them, and real examples for database migrations, config setup, and more.
Docker layer caching can make your builds 10x faster or silently break them. Here's exactly how it works and how to use it properly.
Instead of patching a running server, you replace it entirely with a new one built from a known-good image. Here's what immutable infrastructure actually means, why it matters, and how containers made it the default.
Canary deployments let you test a new version on a small slice of real traffic before going all-in. Here's what it actually means, how it differs from blue-green, and a simple example.
SRE teams talk about SLOs, SLIs, and error budgets constantly, but the terms get used loosely. Here's what each one actually means, with real numbers, and how they connect to decide when to ship vs slow down.
Coolify promises Heroku-style deploys on your own servers, free and open source. I deployed real apps on it to see if it holds up beyond side projects — here's the honest verdict.
Feature flags let you turn features on and off without redeploying code. Here's what they actually are, why DevOps teams care about them, and how to use one safely in production.
Everyone says 'observability' now but most teams are still just doing monitoring. Here's what actually separates the two — and why it matters when your system breaks in a way you didn't expect.
Radius is Microsoft's open source cloud-native app platform, now a CNCF sandbox project. It promises to abstract Kubernetes and cloud resources into developer-friendly 'application' definitions. Here's an honest review of whether it delivers.
Kubernetes 1.30 made Validating Admission Policy GA. It lets you enforce cluster policies using CEL expressions — no OPA, no Gatekeeper, no webhook needed. Here's how it works and when to use it.
Most freshers fail DevOps interviews not because they lack knowledge — they fail because of how they answer. Here are the 10 real mistakes and how to fix each one.
Score is a new developer-centric workload spec that separates what your app needs from how it's deployed. Here's an honest deep-dive: what problem it solves, how it works, where it falls short, and whether you should adopt it.
Continuous profiling tells you exactly which function is burning your CPU or leaking memory — in production, all the time. Here's what it is, how it works, and how to set it up with Pyroscope.
A sidecar container runs alongside your main container in the same pod. Here's what it is, why it's useful, and real examples like log collectors, proxies, and secret injectors.
etcd is Kubernetes' brain — it stores the entire cluster state. Here's what it is, how it works, and why backing it up is the most important thing you can do for your cluster.
The CKA is a hands-on exam, not multiple choice. Here's a day-by-day 30-day study plan, the best resources, and exam tips that actually help you pass.
Progressive delivery is how modern teams deploy safely — canary releases, feature flags, and blue-green deployments. Here's what it means and how it works in Kubernetes.
IT support engineers have more DevOps-transferable skills than they think. Here's the realistic roadmap to transition from L1/L2 support to a DevOps role — skills to learn, what to skip, and how long it takes.
Zero Trust means never trust, always verify — even inside your network. Learn the core principles, how to implement it in Kubernetes and AWS, and the tools DevOps teams actually use.
Container image layers are the building blocks of Docker images. Learn how layers work, why they matter for build speed and security, and how to keep your images lean.
Admission webhooks intercept every Kubernetes API request before it's persisted. Learn how mutating and validating webhooks work, with real examples from OPA, Istio, and custom webhooks.
Multi-tenancy in Kubernetes lets multiple teams share one cluster safely. Learn namespace-based tenancy, vCluster, RBAC, network policies, and when to go single vs multi-tenant.
By default, all pods in Kubernetes can talk to each other. Network Policies let you control exactly which pods can communicate. Here's how they work with practical examples.
Most DevOps learning plans fail because they're too theoretical. Here's a practical 90-day plan focused on building real projects and getting hands-on practice from day one.
Karpenter is replacing Cluster Autoscaler in most EKS deployments. Here's what it actually does, how it's different from Cluster Autoscaler, and when to use it.
DaemonSets ensure a pod runs on every node. Here's what they are, when you need them, and how they differ from Deployments with practical examples.
Chaos engineering sounds like deliberately breaking things. It is — but in a controlled way that makes your systems stronger. Here's what it is, how it works, and how to start.
StatefulSets confuse most beginners. Here's a clear explanation of what they are, how they differ from Deployments, and when you actually need them.
FinOps keeps showing up in job descriptions and team meetings. Here's what it actually means, what DevOps engineers need to know about it, and practical techniques to implement it.
Envoy proxy powers Istio, AWS App Mesh, and many service meshes. Here's what it actually does, why it matters, and how it works — explained simply.
Confused about what an Ingress Controller actually does in Kubernetes? This guide explains it simply with diagrams, examples, and when to use which one.
RBAC in Kubernetes controls who can do what in your cluster. Learn what Roles, ClusterRoles, RoleBindings, and ServiceAccounts are with real examples.
OpenTelemetry (OTel) is the open standard for collecting traces, metrics, and logs. Learn what it is, why it matters, and how to start using it.
CRDs extend the Kubernetes API with your own resource types. Learn what Custom Resource Definitions are, why they exist, and how tools like ArgoCD, Cert-Manager, and Prometheus use them.
How do pods find each other in Kubernetes? Service discovery is the mechanism that lets services communicate without hardcoded IPs. Here's how it works, simply explained.
BuildKit is Docker's modern build engine. It makes your Docker builds faster, more secure, and more efficient. Here's what it actually does and why you should use it.
Every server, container, and cloud VM runs on a Linux kernel. But what does the kernel actually do? Here's a clear explanation of what the Linux kernel is, what it controls, and why it matters for DevOps engineers.
Every container needs a runtime to actually run. Docker has one. Kubernetes has one. They're different. Here's what a container runtime is, why it matters, and how containerd, runc, CRI-O, and Docker relate to each other.
Every Kubernetes pod goes through phases — Pending, Running, Succeeded, Failed, Unknown. Here's what each phase means, what causes pods to get stuck, and how the lifecycle connects to containers, probes, and restarts.
Microservices is an architecture where one big application is split into small, independent services. Here's what that actually means, why companies use it, when it makes sense, and when it doesn't — with real examples.
Terraform modules let you reuse infrastructure code instead of copying and pasting. Here's what a module is, how to write one, how to use one, and why every Terraform project beyond the basics needs them.
Terraform workspaces let you manage multiple environments from a single configuration. Here's how they work, when to use them, and why many teams prefer separate directories instead.
IAM is how AWS decides who can do what. Here's a plain-English explanation of users, groups, roles, and policies — with real examples of how they're used together.
Rolling update keeps your app running during deploys. Recreate kills everything then starts fresh. Here's when to use each, plus Blue-Green and Canary explained simply.
Three tools for running Kubernetes on your laptop. They're not all equal — kind is fastest for CI, k3d is lightest for dev, minikube has the best feature set. Here's the full comparison.
Node affinity lets you control which nodes your pods run on. Here's a plain-English explanation of nodeSelector, nodeAffinity, podAffinity, and taints/tolerations — when to use each.
A PDB prevents Kubernetes from evicting too many pods at once during maintenance. Here's how it works, how to set it up, and the one mistake that causes node drains to hang.
Pods can die and restart with new IPs. A Service gives them a stable address. Here's how ClusterIP, NodePort, and LoadBalancer actually work — with clear examples.
CNI is why your pods can talk to each other — but most engineers don't know how it works. Here's a plain-English explanation of CNI, plugins, and when it matters for you.
gRPC is replacing REST in microservices — but what is it and why should DevOps engineers care? Here's a plain-English explanation with Kubernetes examples.
No experience, no job. Here's exactly how freshers land DevOps internships in 2026 — what to build, where to apply, and what to say in interviews.
Kustomize lets you customize Kubernetes YAML without copying and editing files. Here's what it is, how it works, and when to use it instead of Helm.
YAML is the config language of DevOps — Kubernetes, Docker Compose, GitHub Actions, Ansible all use it. Here's what YAML actually is and how to read and write it without confusion.
Many QA engineers are switching to DevOps — the skills overlap more than you think. Here's the honest roadmap, what to learn, how long it takes, and how to make the move.
An API Gateway sits in front of your backend services and handles auth, routing, rate limiting, and more. Here's what it actually does and when you need one.
Message queues are how distributed systems communicate reliably. Here's what they actually are, why you need them, and how Kafka, RabbitMQ, and SQS differ — explained simply.
DNS is the phonebook of the internet. Here's what it actually does, how it works step by step, and why DevOps engineers need to understand it deeply.
SSH (Secure Shell) is how engineers connect to remote servers. Here's what SSH actually is, how it works, and how to use it — explained without jargon.
SRE is how Google runs production at scale. Here's what it actually means, how it differs from DevOps, and what SREs do day-to-day — explained without jargon.
DevOps is not a tool or a job title — it's a culture. Here's what DevOps culture actually means, why most companies get it wrong, and what it looks like when done right.
Taints and tolerations control which pods can run on which nodes. Here's how they work, why you need them, and real examples for GPU nodes, spot instances, and dedicated workloads.
Docker Compose lets you define and run multi-container applications with a single file. Here's what it does, how it works, and when to use it — explained simply.
Pod Security Admission replaced PodSecurityPolicy in Kubernetes 1.25. Here's what it does, how the three security levels work, and how to enforce it in your cluster.
Kubernetes requests and limits control how much CPU and memory a pod gets. Get them wrong and your pods get throttled, OOMKilled, or evicted. Here's how they actually work.
The best YouTube channels, courses, blogs, and communities for learning DevOps in 2026 — curated for beginners, intermediate engineers, and specialists. Stop watching random tutorials and learn from the best.
Kubernetes nodes are the machines where your containers actually run. Here's what a node is, the difference between worker nodes and control plane nodes, what runs on them, and how to manage node issues.
SSL and TLS are everywhere — HTTPS, certificates, cert-manager, Let's Encrypt. Here's what SSL/TLS actually is, how the handshake works, what certificates do, and what you need to know as a DevOps engineer.
How do Docker containers talk to each other and to the outside world? Here's what Docker networking is, the difference between bridge, host, and overlay networks, and practical examples you'll use every day.
CI/CD is mentioned in every DevOps job description — but what does it actually mean? Here's what Continuous Integration and Continuous Delivery/Deployment are, how they work, and why every team needs them.
Webhooks are how apps talk to each other in real time — but the explanation is always confusing. Here's what a webhook actually is, how it works, how it differs from APIs, and real DevOps examples.
Already a software developer and want to move into DevOps? Here's the exact skills gap to bridge, what to learn first, what to skip, and how to get your first DevOps role in 2026.
Containers lose all data when they stop — Docker volumes fix that. Here's what Docker volumes are, how they work, the difference between volumes, bind mounts, and tmpfs, and when to use each.
Exact skills, timelines, and mindset shifts for moving from junior DevOps to senior — what you need to learn, what to build, and how long it realistically takes.
PersistentVolume, PersistentVolumeClaim, and StorageClass in Kubernetes explained from scratch — how storage works, how to use it, and common mistakes.
LimitRange and ResourceQuota in Kubernetes explained from scratch — what they do, how they differ, and how to set them up with real examples.
Complete CKA exam prep guide for 2026 — what to study, how to practice, which resources actually help, and tips to pass on the first attempt.
HPA in Kubernetes explained from scratch — what it does, how it works, how to set it up, and common mistakes to avoid. No jargon.
Reverse proxy explained simply — what it does, how it's different from a forward proxy, and why Nginx, Traefik, and AWS ALB are everywhere in DevOps.
Terraform state explained simply — what it is, why it exists, where it's stored, and how to manage it safely. No jargon, just clarity.
Deployments run forever. Jobs run once and stop. CronJobs run on a schedule. Here's how both work, when to use them, and simple examples to get started.
Deployment and StatefulSet both manage pods in Kubernetes, but for completely different use cases. Here's when to use each one, explained simply.
Running Kubernetes locally for dev or edge? k3s, k0s, and minikube each solve different problems. Here's a full comparison to help you pick the right one.
A DaemonSet ensures one pod runs on every node in your cluster. Here's what it is, how it works, and when to use it — explained simply with examples.
You don't need expensive hardware to practice DevOps. Here's how to build a complete home lab with Kubernetes, CI/CD, and monitoring using free tools and cloud free tiers.
ConfigMaps and Secrets separate configuration from code in Kubernetes. Here's what they are, how they work, and when to use each one — explained simply.
You're a sysadmin with Linux, scripting, and networking skills. Here's exactly how to make the DevOps jump — what to learn, what to skip, and how to get your first DevOps title.
Kubernetes Ingress routes external HTTP/HTTPS traffic to your services. Here's what it is, how it works, and how to set one up — explained simply.
Open source contributions are the fastest way to build credibility, get noticed by top companies, and level up your DevOps skills. Here's exactly how to start — from finding projects to getting your first PR merged.
Jenkins is the old reliable. Tekton is cloud-native, Kubernetes-native, and built for containers. Here's a detailed comparison so you can pick the right CI tool for your cluster.
eBPF lets you run custom code inside the Linux kernel safely — without writing kernel modules or rebooting. It's why Cilium is fast, why Datadog Agent is lightweight, and why the future of Kubernetes networking looks different. Here's what it actually is.
Stop duplicating Terraform code for dev, staging, and prod. Use Terraform workspaces to manage multiple environments from one codebase. Step-by-step guide with real AWS examples.
mTLS means both sides of a connection verify each other's identity. It's the backbone of zero-trust networking in Kubernetes service meshes. Here's how it works in plain language.
Namespaces in Kubernetes divide your cluster into virtual sections. Here's what they are, why they matter, and how to use them.
Load balancers are everywhere in DevOps — but most beginners don't fully understand how they work. Here's a clear, simple explanation with real examples.
Kubernetes Operators sound complex but they solve a simple problem: automating the management of stateful applications. Here's what they are and how they work.
Service Accounts and RBAC confuse most beginners. Here's what they are, why they exist, and how to set them up correctly.
What is a container registry, why do you need one, and which one should you use? Docker Hub vs ECR vs GCR vs GitHub Container Registry — simply explained.
Step-by-step guide to building a real multi-node Kubernetes cluster using kubeadm — no managed services, no shortcuts.
Helm solves one of the most painful parts of Kubernetes — managing all those YAML files. Here's what it is, how it works, and why you need it.
These resume mistakes are why DevOps engineers with real skills don't get callbacks. Fix them and watch your interview rate improve.
Observability explained in plain English — what it means, how it's different from monitoring, the three pillars (metrics, logs, traces), and why every DevOps engineer needs to understand it.
GitOps explained in plain English — what it is, how it's different from traditional CI/CD, and how tools like ArgoCD and Flux work. No jargon.
No experience, no referrals — here's the exact roadmap freshers are using to land their first DevOps role in 2026. Skills, projects, and what actually gets you hired.
Infrastructure as Code (IaC) explained in plain English — what it is, why every DevOps team uses it, and how to get started with Terraform and Pulumi in 2026.
Service mesh sounds complicated but the concept is simple. Here's what it actually does, why teams use it, and whether you need one — explained without the buzzwords.
Step-by-step guide to migrating from Ingress-NGINX to Kubernetes Gateway API. Includes YAML examples, implementation choices, testing strategy, and cutover plan.
Step-by-step guide to setting up Kubernetes VPA with In-Place Pod Resize. Auto-scale CPU and memory without pod restarts. Full tutorial with YAML examples.
ImagePullBackOff is one of the most common Kubernetes errors. This guide covers every root cause — wrong image names, missing auth, network issues, rate limits — with step-by-step debugging and fixes.
A practical step-by-step guide to setting up GitLab CI/CD pipelines from zero — covering runners, pipeline stages, Docker builds, deployment to Kubernetes, and best practices.
HashiCorp Vault is the industry standard for secrets management. This step-by-step guide shows you how to install Vault, configure it, and integrate it with Kubernetes.
Learn Ansible from zero — install it, configure SSH, write your first playbook, use variables and loops, and automate real server tasks step by step.
The Kubernetes Ingress API is being replaced by the Gateway API. Here's a complete step-by-step guide to setting it up with Nginx Gateway Fabric and migrating from Ingress.
Master Docker Compose in 2026. Learn how to write docker-compose.yml files, manage volumes, networks, environment variables, health checks, and run multi-container apps the right way.
The complete Linux command reference for DevOps engineers in 2026. Master file management, process control, networking, system monitoring, SSH, permissions, and shell scripting with real-world examples.
What is Docker, why engineers use it, and how to get started with containers from scratch. A practical, no-fluff guide.
Understand every component of Kubernetes — Control Plane, Worker Nodes, Pods, Services, and Deployments — with clear diagrams and practical examples.