Install Docker on AlmaLinux 9

Step 1 – Install

dnf config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
dnf install -y docker-ce docker-ce-cli containerd.io docker-compose-plugin
systemctl enable --now docker

Step 2 – Add user to docker group

usermod -aG docker $USER && newgrp docker

Step 3 – Verify

docker --version
docker run --rm hello-world

Step 4 – Example compose.yml

services:
  web:
    image: nginx:alpine
    ports: ["80:80"]
  db:
    image: mysql:8
    environment:
      MYSQL_ROOT_PASSWORD: rootpass
      MYSQL_DATABASE: appdb
    volumes: [mysql_data:/var/lib/mysql]
volumes:
  mysql_data:

docker compose up -d