Install Docker Compose on AlmaLinux 9 with Docker Engine and the maintained Compose CLI plugin. In roughly ten minutes, you will start a two-service test project, check its health, and keep its web port private.<\/p>\n\n\n\n
AlmaLinux 9 uses DNF and firewalld. The commands below install Docker’s RHEL-compatible packages; if you are already using Podman or another container runtime, check its workloads before changing packages.<\/p>\n\n\n\n
Checking the release avoids adding an Enterprise Linux 8 repository to an AlmaLinux 9 machine.<\/p>\n\n\n\n
~~~bash . \/etc\/os-release printf ‘%s\\n’ “$PRETTY_NAME” uname -m sudo dnf upgrade -y ~~~<\/p>\n\n\n\n
The first two checks should identify AlmaLinux 9 and a 64-bit architecture:<\/p>\n\n\n\n
~~~text AlmaLinux 9.x (Emerald Puma) x86_64 ~~~<\/p>\n\n\n\n
The minor release and update count will vary. Resolve any DNS, mirror, or package-signature error before continuing.<\/p>\n\n\n\n
The Docker repository provides the Engine, CLI, Buildx, and Compose plugin as packages that DNF can update together.<\/p>\n\n\n\n
~~~bash sudo dnf install -y dnf-plugins-core ca-certificates sudo dnf config-manager –add-repo https:\/\/download.docker.com\/linux\/rhel\/docker-ce.repo sudo dnf makecache dnf repolist –enabled | grep -i docker ~~~<\/p>\n\n\n\n
You should see Docker’s stable repository in the final output. These are the repository steps from Docker’s RHEL installation guide<\/a>, using AlmaLinux 9’s RHEL-compatible package interface.<\/p>\n\n\n\n Installing the plugin with the Engine gives the Docker CLI a compose subcommand and avoids the unsupported legacy standalone executable.<\/p>\n\n\n\n ~~~bash sudo dnf install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin sudo systemctl enable –now docker sudo systemctl is-active docker sudo docker version –format ‘Client {{.Client.Version}} \/ Server {{.Server.Version}}’ sudo docker compose version ~~~<\/p>\n\n\n\n The service should report active, followed by version strings. Exact versions change as Docker publishes updates:<\/p>\n\n\n\n ~~~text active Client 29.x \/ Server 29.x Docker Compose version vX.Y.Z ~~~<\/p>\n\n\n\n Run Docker’s small smoke test. It downloads a public image, starts a temporary container, prints a message, and removes the container when it exits.<\/p>\n\n\n\n ~~~bash sudo docker run –rm hello-world ~~~<\/p>\n\n\n\n Near the end, expect output containing:<\/p>\n\n\n\n ~~~text Hello from Docker! Your installation appears to be working correctly. ~~~<\/p>\n\n\n\n The Docker socket is root-owned by default, so add only the trusted account that will manage containers instead of making the socket broadly writable.<\/p>\n\n\n\n Replace YOUR_LINUX_USER with the username used for SSH:<\/p>\n\n\n\n ~~~bash sudo usermod -aG docker YOUR_LINUX_USER ~~~<\/p>\n\n\n\n Log out and reconnect so the new group membership is loaded, then check it:<\/p>\n\n\n\n ~~~bash id -nG docker info –format ‘Server {{.ServerVersion}}’ ~~~<\/p>\n\n\n\n The group list should include docker, and docker info should print the Engine version. The Docker group grants root-equivalent control over the host, so add only accounts you trust. If you prefer not to use the group, keep the sudo prefix on later Docker commands.<\/p>\n\n\n\n This project pairs Caddy, which serves a local page, with Redis, which stays on Compose’s private network. The loopback binding lets you test the result without exposing port 8090 to the internet.<\/p>\n\n\n\n ~~~bash mkdir -p ~\/compose-alma9\/site cd ~\/compose-alma9 printf ‘%s\\n’ ‘AlmaLinux 9 Docker Compose is working.’ > site\/index.html ~~~<\/p>\n\n\n\n Create the Caddy configuration:<\/p>\n\n\n\n ~~~bash tee Caddyfile >\/dev\/null <<‘EOF’ :8090 { root * \/srv file_server } EOF ~~~<\/p>\n\n\n\n Create compose.yaml:<\/p>\n\n\n\n ~~~bash tee compose.yaml >\/dev\/null <<‘EOF’ services: web: image: caddy:2-alpine restart: unless-stopped ports:<\/p>\n\n\n\n cache: image: redis:7-alpine restart: unless-stopped command: [“redis-server”, “–save”, “”, “–appendonly”, “no”] healthcheck: test: [“CMD”, “redis-cli”, “ping”] interval: 5s timeout: 3s retries: 10 EOF ~~~<\/p>\n\n\n\n The :Z mount option assigns SELinux labels suitable for private container mounts. Redis has no published port, and the sample disables persistence because it is only an installation test; use a password, persistent storage, and a backup plan for a real cache or database. The service and volume syntax follows Docker’s Compose file reference<\/a>.<\/p>\n\n\n\n Rendering the file before startup catches YAML and interpolation errors without creating containers.<\/p>\n\n\n\n ~~~bash docker compose config –quiet docker compose pull docker compose up -d docker compose ps ~~~<\/p>\n\n\n\n The first command is silent when the file is valid. After the images download, the table should show a running web service and a healthy cache:<\/p>\n\n\n\n ~~~text NAME SERVICE STATUS PORTS compose-alma9-web-1 web Up 127.0.0.1:8090->8090\/tcp compose-alma9-cache-1 cache Up (healthy) ~~~<\/p>\n\n\n\n Container names may differ if you choose another directory or set a Compose project name.<\/p>\n\n\n\n Use one HTTP request, one Redis health check, and a short log view to prove that the plugin can control the project and that both services are responding.<\/p>\n\n\n\n ~~~bash curl –fail –silent http:\/\/127.0.0.1:8090 docker compose exec -T cache redis-cli ping docker compose logs –tail=20 web cache ~~~<\/p>\n\n\n\n The first two commands should return:<\/p>\n\n\n\n ~~~text AlmaLinux 9 Docker Compose is working. PONG ~~~<\/p>\n\n\n\n Because Caddy listens only on loopback, a remote browser cannot reach it directly. To view it from your workstation, create an SSH tunnel with ssh -L 8090:127.0.0.1:8090 USER@SERVER_IP, then open http:\/\/127.0.0.1:8090 locally.<\/p>\n\n\n\nStep 3: Install Docker Engine and Compose<\/h2>\n\n\n\n
Step 4: Allow your SSH account to use Docker<\/h2>\n\n\n\n
Step 5: Create a small Compose project<\/h2>\n\n\n\n
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Step 6: Render and start the services<\/h2>\n\n\n\n
Verify Docker Compose on AlmaLinux 9<\/h2>\n\n\n\n