Tag: containers

Cleaning Up Docker Disk Space the Right Way

docker system prune is useful but risky. Learn what each cleanup command does and how to check disk usage safely.

Stop Putting Passwords in Docker ENV

ENV bakes secrets into layers visible in docker history. Use BuildKit --secret, runtime vars, or .env files.

Why the `latest` Docker Tag Is Lying to You

latest doesn't mean newest. Learn why pinning versions and digests matter for reproducible deployments.

Multi-Platform Docker Builds with buildx

Build ARM64 and AMD64 images from one machine using Docker buildx. Setup, syntax, pushing multi-arch manifests, and when you actually need it.

Docker Network Aliases: The Feature Nobody Uses

Network aliases give containers multiple DNS names. Perfect for blue-green deploys and service discovery patterns.

Docker Healthcheck Patterns That Actually Work

Master Docker HEALTHCHECK syntax. Learn what checks work, how to tune interval/timeout/retries, and integrate with orchestration.

Running Docker Containers as Non-Root (And Why You Should)

Running as root in containers is a security foot-gun. Learn the USER instruction and numeric UID/GID pattern.

Docker Container Labels: The Metadata You're Ignoring

Docker labels are free metadata for filtering, routing, and documentation. Learn label conventions and leverage them with filters and tools.

Why Docker Builds Are Slow: Layer Cache Explained

Layer caching is your build's BFF. Learn why copying files early kills the cache and how to fix it.

Docker Exit Codes: Why Your Container Keeps Restarting

Decode Docker exit codes: 0 (success), 1 (app error), 125/126/127 (Docker errors), 137 (OOM), 143 (SIGTERM). Debug restarts in minutes.

The .dockerignore File You're Not Writing

Missing .dockerignore bloats build context, slows builds, and leaks secrets. Here's the one you should copy-paste.

Why Your Docker Logs Are Eating Your Disk

Docker's default JSON logging driver writes unbounded logs to disk. Learn how to set log rotation and reclaim your storage.