Docker Restart Policies in Docker Compose

The Question

If you set restart: unless-stopped in your docker-compose.yml, will the containers automatically restart after a system reboot?

Yes, they will — as long as the Docker daemon itself starts on boot.

Restart Policy Overview

Docker provides four restart policies:

Policy On Crash On Reboot After Manual docker stop + Reboot
no ❌ ❌ ❌
on-failure ✅ ❌ ❌
unless-stopped ✅ ✅ ❌
always ✅ ✅ ✅

unless-stopped vs always

The only difference between unless-stopped and always is:

  • always: The container restarts no matter what — even if you manually stopped it before the reboot.
  • unless-stopped: The container restarts on reboot unless it was explicitly stopped with docker stop before the system went down.

Example

services:
  web:
    image: nginx:latest
    restart: unless-stopped

With this configuration:

  • If the container crashes → it will be restarted automatically.
  • If the system reboots → it will be restarted automatically.
  • If you run docker stop web and then reboot → it will not be restarted.

Prerequisites

The restart policy only works if the Docker daemon is running after the system boots. Make sure Docker is enabled to start on boot:

Linux:

sudo systemctl enable docker

Windows / macOS (Docker Desktop):

Enable “Start Docker Desktop when you sign in” in Docker Desktop settings.

Recommendation

For most production services, unless-stopped is the best default. It gives you automatic recovery from crashes and reboots while still respecting your manual docker stop commands. Use always only when you want a container to run unconditionally regardless of prior state.