Working with Docker Stacks

1. Creating Stack Compose File

Field	Description	Example
version	Version of the Compose file format	`'3.8'`
services	Defines the services that make up the stack	`services: web: image: nginx`
volumes	Defines volumes to be used by services	`volumes: data_volume`
networks	Defines networks to be used by services	`networks: frontend`

Example: Basic Stack Compose File

version: '3.8'
services:
  web:
    image: nginx
    ports:
      - "80:80"
  database:
    image: mysql:8.0
    environment:
      MYSQL_ROOT_PASSWORD: password
volumes:
  data_volume:
networks:
  frontend:

2. Deploying Stacks

Example: Deploy a stack using docker stack deploy

docker stack deploy -c docker-compose.yml myapp

Option	Values	Description
-c, --compose-file	`docker-compose.yml`	Path to the Compose file
--detach	`true`	Run in detached mode (default: true)
--resolve-image	`always`	Resolve image tags to digests (default: `always`)

Note: The stack must be deployed to a Docker Swarm cluster. Use docker swarm init to initialize the swarm if needed.

Warning: Ensure that all services in the Compose file have unique names to avoid conflicts during deployment.

3. Listing Stacks

Command	Description	Options
docker stack ls	List all running stacks	`-f, --filter` Filter output `--format` Format output using Go template

Example: List all stacks

<pre><code>docker stack ls
</code></pre></div>

Example: List stacks with custom format

<pre><code>docker stack ls --format "{{.Name}} - {{.Services}} services"
</code></pre></div>

4. Listing Stack Services

Command	Description	Options
docker stack services <stack_name>	List all services in a stack	`--format` to format output, `--filter` to filter results

Example: Listing services in a stack

docker stack services myapp

Note: The docker stack services command lists all services defined in the specified stack, including their status, replicas, and other relevant details.

5. Viewing Stack Tasks

Task ID	Service Name	Status	Created
task-123abc	`web`	RUNNING	2026-01-15 10:30
task-456def	`db`	STOPPED	2026-01-14 09:15

Example: View stack tasks using CLI

docker stack tasks myapp

Note: The docker stack tasks command lists all tasks in a stack, showing their current status and associated service.

6. Configuring Stack Networks

Network Property	Description	Default Value	Notes
driver	Driver to use for the network	`overlay`	Must be `overlay` for swarm mode
attachable	Allow external containers to connect	`false`	Enables non-service containers to join
internal	Restrict external access	`false`	Prevents access from outside the swarm
ipv6	Enable IPv6 support	`false`	Requires Docker daemon config

Example: Create an Internal Stack Network

docker network create \
  --driver overlay \
  --internal \
  --subnet 10.0.9.0/24 \
  stack-net

Note: Internal networks do not have access to the host network.

Example: Attach Service to Custom Network

version: '3.8'
services:
  web:
    image: nginx
    networks:
      - stack-net

networks:
  stack-net:
    external: true

7. Configuring Stack Volumes

Volume Type	Description	Usage
bind	Mounts a host directory as a volume	`docker stack deploy -c docker-compose.yml myapp`
volume	Creates a named volume managed by Docker	`docker volume create myvolume`
tmpfs	Mounts a temporary filesystem in memory	`-t tmpfs -v /tmp`

Example: Bind Mount Volume

version: '3.8'
services:
  web:
    image: nginx
    volumes:
      - /host/data:/usr/share/nginx/html

Example: Named Volume

version: '3.8'
services:
  db:
    image: postgres
    volumes:
      - db_data:/var/lib/postgresql/data

volumes:
  db_data:

Note: Volume configuration in stacks is managed via docker-compose.yml files, not directly through CLI commands.

8. Using Stack Secrets

Property	Description	Example
secret.name	Name of the secret to be used in the stack	`db_password`
secret.source	Source of the secret (file or literal)	`file` or `literal`
secret.file	Path to the file containing the secret (when source is file)	`/path/to/secret.txt`
secret.literal	Literal value of the secret (when source is literal)	`my_secret_value`

Example: Define a secret in a stack compose file

version: "3.8"
services:
  web:
    image: nginx
    secrets:
      - db_password

secrets:
  db_password:
    file: ./db_password.txt

Example: Using a literal secret

version: "3.8"
services:
  web:
    image: nginx
    secrets:
      - api_key

secrets:
  api_key:
    external: true

Note: Secrets are mounted as files in the service's filesystem, typically under /run/secrets.

9. Using Stack Configs

Config Name	Source	Description	Usage
config.name	`docker stack config`	Name of the configuration	Used to reference the config in services
config.data	`docker config create`	Content of the configuration	Can be a file or string
config.file	`docker config create`	Path to file for config data	Used when reading from local files

Example: Create a Stack Config

docker config create my-config /path/to/config.json

Example: Use Config in Stack

version: '3.8'
services:
  web:
    image: nginx
    configs:
      - my-config
configs:
  my-config:
    external: true

Note: Stack configs are global and can be shared across services in a stack.

10. Updating Stack Deployments

Command	Description	Notes
docker stack deploy	Update a stack with new configuration	Use `--compose-file` to specify updated compose file

Example: Update stack deployment

docker stack deploy -c updated-compose.yml myapp

Note: Changes to services or configs will be applied during deployment

Warning: Rolling updates may cause downtime depending on service configuration

Option	Description	Default
--compose-file	Path to updated compose file	None
--with-registry-auth	Use registry auth from local config	false

11. Monitoring Stack Health

Command	Description	Example
docker stack ps	Lists tasks in a stack	`docker stack ps myapp`
docker stack ls	Lists all stacks	`docker stack ls`
docker service logs	Displays logs for a service	`docker service logs myapp_web`

Example: Check stack task status

docker stack ps myapp
ID             NAME              IMAGE           NODE            DESIRED STATE   CURRENT STATE           ERROR   PORTS
abc123         myapp_web.1       nginx:latest    node-1          Running         Running 2 hours ago

Note: Use docker stack ps --format json for structured output.

Warning: If a task is in Failed state, check logs with docker service logs.

12. Removing Stacks

Command	Description	Flags
docker stack rm	Removes a stack from the swarm	`--force` - Force removal even if stack is in use

Example: Remove a stack

docker stack rm myapp

Note: This command removes all services, networks, and volumes associated with the stack.

Warning: Removing a stack will delete all resources created by it. Ensure data is backed up before removal.