Tag: devops

The -v and --mount flags for Docker volumes explained, bind mounts vs named volumes, read-only, propagation, and tmpfs options.

Move Docker images between hosts without a registry using docker save and docker load, air-gapped deployments made simple.

CMD and ENTRYPOINT both define what runs in a container but work differently, exec vs shell form, and how they interact when combined.

Use docker cp to move files between running containers and your host machine, no volumes needed for one-off file transfers.

COPY and ADD look similar but ADD auto-extracts tarballs and fetches URLs, know when each is appropriate and why COPY is usually better.

Add load balancing and failover to your Docker setup using Swarm, nginx, HAProxy, and Keepalived, high availability without Kubernetes.

Access services on the host machine from inside a Docker container using host-gateway or host.docker.internal, no hardcoded IPs.

Containers share the kernel; VMs have their own. Understand the isolation trade-offs, overhead differences, and when to use which.

Run multiple commands in one docker exec call by piping a heredoc to the container shell, chain dependent steps and skip repeated container roundtrips.

Shell globbing breaks inside docker exec because of how args are parsed, here's how to pass wildcards and asterisks correctly.

Master tmux for dev work: sessions, windows, panes, layout scripting, hooks, and pane syncing, the commands that turn one terminal into many.

Ansible configures servers; Terraform provisions infrastructure, learn when to use each, how they overlap, and why you probably need both.