☸️Kubernetes Core Concepts
Stop drowning in 30+ resource types. Build the mental model one primitive at a time -- pods, deployments, services, ingress, config -- then deploy a real app with rolling updates and health checks.
Phase 1The Reconciliation Loop Behind Everything
See the reconciliation loop behind every K8s command
Kubernetes is a loop, not a command runner
6 minKubernetes is a loop, not a command runner
The control plane is a database with watchers
6 minThe control plane is a database with watchers
A pod is one deployable unit, usually one container
6 minA pod is one deployable unit, usually one container
Scheduling is a two-phase scoring game
6 minScheduling is a two-phase scoring game
Phase 2Minimal YAML for Real Workloads
Write minimal YAML for pods, deployments, and services
Deployments are just pod factories with versions
7 minDeployments are just pod factories with versions
Labels are how every controller finds its work
6 minLabels are how every controller finds its work
Requests reserve, limits cap -- they are not the same
7 minRequests reserve, limits cap -- they are not the same
Liveness and readiness answer different questions
7 minLiveness and readiness answer different questions
Namespaces are walls, not folders
6 minNamespaces are walls, not folders
Phase 3Services, Ingress, and Config Wiring
Wire services, ingress, config, and secrets together
A Service is a stable name for a moving target
6 minA Service is a stable name for a moving target
Ingress is a shared LoadBalancer, not a Service type
7 minIngress is a shared LoadBalancer, not a Service type
Baking config into images is a testability bug
6 minBaking config into images is a testability bug
Secrets are ConfigMaps with a warning label
7 minSecrets are ConfigMaps with a warning label
Phase 4Ship a Real App with Rolling Updates
Deploy a real app with rolling updates
Ship a real two-tier app with zero-downtime rollouts
20 minShip a real two-tier app with zero-downtime rollouts
Frequently asked questions
- What's the difference between a pod and a container?
- This is covered in the “Kubernetes Core Concepts” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- Why do I need a Deployment if I already have a Pod?
- This is covered in the “Kubernetes Core Concepts” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- When should I use a Service vs an Ingress?
- This is covered in the “Kubernetes Core Concepts” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- How does Kubernetes actually decide where to run my pod?
- This is covered in the “Kubernetes Core Concepts” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
- What's the minimum YAML I need to deploy a real app?
- This is covered in the “Kubernetes Core Concepts” learning path. Start with daily 5-minute micro-lessons that build from fundamentals to hands-on application.
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