Docker & Containers for Production Sysadmins

Part I

Foundations

Containers vs VMs, OCI ecosystem, Docker architecture, Linux primitives.

6 lessons

Part II

Linux Internals

Namespaces, cgroups v2, OverlayFS, capabilities, the kernel features Docker relies on.

8 lessons

Part III

Installation & Daemon

Repositories, version pinning, Docker Engine, containerd, runc, systemd, daemon.json.

7 lessons

Part IV

Images

Layers, manifests, digests, tags, multi-platform, inspection, lifecycle.

6 lessons

Part V

Dockerfiles & BuildKit

Instructions, caching, multi-stage, secrets, reproducibility, minimal images.

8 lessons

Part VI

Container Lifecycle

run / create / start / stop / exec / signals / PID 1 / graceful shutdown.

6 lessons

Part VII

Networking

Namespaces, veth, bridge, host, macvlan, ipvlan, DNS, published ports.

8 lessons

Part VIII

Storage

Writable layers, volumes, bind mounts, tmpfs, UID/GID, network storage.

7 lessons

Part IX

Docker Compose

Services, networks, volumes, secrets, healthchecks, profiles, production patterns.

7 lessons

Part X

Production Architecture

Host design, reverse proxies, TLS, segmentation, capacity, operational boundaries.

6 lessons

Part XI

Container & Host Security

Capabilities, seccomp, AppArmor, rootless, no-new-privileges, Docker socket risk.

6 lessons

Part XII

Supply Chain

Image provenance, SBOM, CVEs, scanners, signing, Cosign.

6 lessons

Part XIII

Registries

Docker Hub, private registries, auth, digests, retention, backup.

6 lessons

Part XIV

Secrets

Build secrets, runtime secrets, external secret managers.

6 lessons

Part XV

Resource Controls

CPU, memory, swap, PIDs, I/O, OOM behaviour, noisy neighbours.

6 lessons

Part XVI

Performance

Storage drivers, image size, startup, eBPF, Linux perf tools.

6 lessons

Part XVII

Logging

Drivers, rotation, journald, syslog, Fluent Bit, Loki.

6 lessons

Part XVIII

Monitoring

Host, Docker, container, application metrics; Prometheus, cAdvisor, Grafana.

6 lessons

Part XIX

Observability

Metrics, logs, traces, OpenTelemetry, Tempo, end-to-end correlation.

6 lessons

Part XX

Health & Failure Detection

Healthchecks, restart policies, dependency failures.

6 lessons

Part XXI

Backup

Volumes, bind mounts, application-consistent backups, offsite copies, restore tests.

6 lessons

Part XXII

Disaster Recovery

RPO/RTO, destroyed-host recovery, restore, exercise cadence.

6 lessons

Part XXIII

High Availability

Standalone Docker limits, multi-host patterns, external load balancing, when orchestration is needed.

6 lessons

Part XXIV

Reverse Proxies & TLS

nginx, HAProxy, Traefik, Caddy, HTTP versions, WebSockets.

6 lessons

Part XXV

Certificates & PKI

TLS, ACME, automated renewal, failure modes.

6 lessons

Part XXVI

DNS & Service Discovery

Embedded DNS, troubleshooting.

6 lessons

Part XXVII

Firewalls

nftables, iptables, ufw, Docker port exposure, effective validation.

6 lessons

Part XXVIII

Maintenance

Disk consumption, prune, build cache, image cleanup.

6 lessons

Part XXIX

Docker Upgrades

Change review, backups, rollback, maintenance window.

6 lessons

Part XXX

Host Maintenance

Kernel updates, reboots, security patching, filesystem maintenance.

6 lessons

Part XXXI

Troubleshooting

Startup, networking, DNS, storage, OOM, TLS, daemon, logging, registry, dependencies.

6 lessons

Part XXXII

Docker Internals

dockerd, containerd, shim, runc, OCI runtime lifecycle.

6 lessons

Part XXXIII

Incident Response

Triage, evidence, containment, root cause, recovery, prevention.

6 lessons

Part XXXIV

Capacity Planning

CPU, memory, disk, network, growth, operational headroom.

6 lessons

Part XXXV

Production Hardening

Host, daemon, container, network, storage, image, secrets, monitoring, backup checklists.

6 lessons

Part XXXVI

Automation

Shell, systemd, Ansible, CI/CD concepts.

6 lessons

Part XXXVII

Orchestration Transition

Why orchestrators exist; Swarm, Kubernetes, Nomad at a glance.

6 lessons

Part XXXVIII

Capstone

A complete production Docker environment, end-to-end.

6 lessons

Part XXXIX

Break/Fix Scenarios

Deliberate operational incidents.

0 lessons

Part XL

Final Assessment

Production-readiness examination.

0 lessons