what is the best approach to managing docker containers – is kubernetes the best approach? what about terraform?
Short answer: there’s no single “best” — choose based on scale, team skills, and requirements.
When to use Docker Compose (or Docker + Terraform local-exec)
- Best for: single-host or small clusters, local dev, simple multi-container apps.
- Pros: simple, fast iteration, easy to understand, works with existing compose files and .env.
- Cons: limited scheduling, no built-in scaling, single-host failure domain.
When to use the Docker provider in Terraform
- Best for: infra-as-code on a single host where you want Terraform-managed container lifecycle.
- Pros: Terraform state, resource-level control, integrates with other IaC (networks, volumes).
- Cons: Not a cluster scheduler, binds you to Docker host(s), less suitable for multi-node deployments.
When to use Kubernetes
- Best for: production at scale, multi-node clusters, microservices requiring autoscaling, self-healing, advanced networking, and rollout strategies.
- Pros: mature scheduling, autoscaling, service discovery, declarative API, ecosystem (Helm, operators), cloud-managed offerings (EKS/GKE/AKS).
- Cons: operational complexity, steeper learning curve, higher resource overhead, more tooling/observability needed.
When to use Terraform (in general)
- Best for: provisioning and managing infrastructure (VMs, networks, cloud services) and for declaratively managing resources that expose providers.
- Pros: reproducible infra, stateful plans, multi-cloud support, integrates with Kubernetes provider and other APIs.
- Cons: not a runtime orchestrator (doesn’t replace a container scheduler like K8s); using Terraform with local-exec to run docker-compose is pragmatic but treats runtime as an external side-effect.
Decision guidance (decisive defaults)
- Small app, single host, low ops capacity ? Docker Compose (or Docker + Terraform for infra) is simplest.
- Need IaC, predictable deployments, few hosts ? Terraform + Docker provider gives Terraform-managed containers.
- Production-ready, multi-node, high-availability, autoscaling, frequent deployments ? Kubernetes (managed K8s if you want less ops).
- Hybrid: use Terraform to provision cloud infra (VMs, managed K8s) and use K8s/Helm or Docker Compose for runtime manifests.
Practical recommendation
- Start simple: use Compose or Docker provider for dev and small staging.
- Use Terraform to provision infra (networks, storage, managed DBs).
- Move to Kubernetes when you need scaling, multi-node resilience, or sophisticated deployment patterns; prefer a managed Kubernetes service to reduce operational burden.
If you tell me your app size, traffic expectations, and ops experience, I’ll give a specific recommendation and a migration plan.
small production sites – 8 websites with traffic less than 100 a day
For 8 small production sites with <100 visits/day each, use a simple, low-op, reliable stack:
Recommended setup
- Host: single small VPS (or 2 for redundancy if budget allows).
- Container runtime: Docker Compose for simple multi-service apps on one host.
- Orchestration: skip Kubernetes (overkill).
- IaC: use Terraform to provision the VPS and networking; use docker-compose for runtime and have Terraform run Compose (or use cloud-init/Ansible).
- Data persistence: use host bind mounts or Docker volumes for site data and database files; keep regular backups.
- Databases: run MariaDB/Postgres in containers or use a managed DB if available and affordable.
- Secrets: store credentials outside .env in a secrets manager or at minimum use env files with restricted perms.
- Monitoring & backups: lightweight monitoring (Prometheus/Netdata) + automated nightly backups of DB and site files to remote storage.
- TLS: automate with Let’s Encrypt (certbot or Traefik proxy with ACME).
- Reverse proxy: use Traefik or Nginx proxy in front to route domains and handle TLS.
- Deployment: CI pipeline (GitHub Actions/GitLab CI) to build images and run docker compose pull + up on deploy, or use Terraform local-exec to trigger compose.
Why this fits
- Low traffic ? minimal resource needs; Compose is simple and easy to maintain.
- Terraform for infra gives reproducible provisioning without adding runtime complexity.
- Managed services (DB, object store) are optional tradeoffs for less ops.
Minimal architecture example
- VPS (2 vCPU, 4GB RAM) running Docker + Docker Compose
- Services per host: reverse-proxy (Traefik), 8 site containers, 1 MariaDB, optional backup & monitoring containers
- Data: /srv/sites/, /srv/mariadb (bind mounts)
- Backups to S3-compatible storage daily