Docker & Containerization

Port Publishing and Host Networking

30 min Lesson 20 of 30

Port Publishing and Host Networking

This lesson deepens Docker & Containerization using the same subject areas emphasized by official documentation: Docker docs: Dockerfile reference, image layers, registries, networking, volumes, Compose and runtime operations. The goal is to turn Port Publishing and Host Networking into a production skill: you should know the concept, the configuration surface, the safety controls, the operational checks, and the rollback path.

This course is being expanded as an A-to-Z DevOps path. Each lesson is mapped to documentation concepts first, then translated into production workflows, review checklists, and exercises.

Documentation Coverage

  • Core terms and object model for this topic.
  • Configuration options, defaults, and lifecycle behavior from the docs.
  • Security, reliability, and ownership boundaries.
  • Validation steps before and after the change.
  • Common failure modes and diagnostic signals.

Production Implementation Flow

  1. Define the source of truth: Git, configuration, API, state file, or control plane.
  2. Design the safest repeatable workflow, including dry-run or plan output where possible.
  3. Attach CI/CD, policy, security, and peer-review gates.
  4. Observe metrics, logs, events, or traces after the change.
  5. Document rollback, escalation owner, and evidence for the change record.
docker build --pull --tag registry.example.com/app:release .
docker scout cves registry.example.com/app:release
docker run --rm --read-only --cap-drop=ALL registry.example.com/app:release ./healthcheck

Mastery Standard

You understand Port Publishing and Host Networking when you can explain it, configure it, test it, monitor it, and recover it under incident pressure without relying on undocumented manual steps.

When a topic appears in official docs, do not stop at syntax. Ask how it affects reliability, security, cost, delivery speed, and support ownership.
Practice: create a mini runbook for Port Publishing and Host Networking: prerequisites, commands or pipeline steps, verification checks, risks, rollback, and escalation contacts.