docker compose up and down - Step-by-Step Execution

Process Flow - docker compose up and down

Start: docker-compose.yml file ready

↓

Run: docker compose up

↓

Docker reads config

↓

Create and start containers

↓

Containers running

↓

Run: docker compose down

↓

Stop and remove containers

↓

Cleanup networks (volumes w/ --volumes)

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All stopped and cleaned

This flow shows how docker compose up starts containers from the config, and docker compose down stops and cleans them.

Execution Sample

Docker

docker compose up
# Starts containers

docker compose down
# Stops and removes containers

This code starts containers defined in docker-compose.yml, then stops and removes them.

Process Table

Step	Command	Action	Result	State Change
1	docker compose up	Reads docker-compose.yml	Configuration loaded	Ready to create containers
2	docker compose up	Creates containers	Containers created	Containers exist but not running
3	docker compose up	Starts containers	Containers running	Containers running
4	docker compose up	Output logs	Shows container logs	Running state visible
5	docker compose down	Stops containers	Containers stopped	Containers stopped
6	docker compose down	Removes containers	Containers removed	No containers exist
7	docker compose down	Removes networks (volumes w/ --volumes)	Cleanup done	No networks remain (volumes persist by default)

💡 All containers stopped and removed, environment cleaned up (volumes persist unless --volumes)

Status Tracker

Resource	Start	After 'up' command	After 'down' command
Containers	None	Created and running	Removed
Networks	None	Created	Removed
Volumes	None	Created if defined	Removed if defined w/ --volumes

Key Moments - 3 Insights

Why do containers still exist after 'docker compose up' but before 'docker compose down'?

Because 'docker compose up' creates and starts containers, so they exist and run until 'docker compose down' stops and removes them, as shown in steps 3 and 5 of the execution table.

Does 'docker compose down' delete volumes by default?

No, volumes are only removed if you add the --volumes flag. The execution table and variable_tracker show volumes handling.

What happens if you run 'docker compose up' again while containers are running?

Docker Compose will detect running containers and recreate or reuse them depending on changes, but this is beyond the simple up/down flow shown here.

Visual Quiz - 3 Questions

Look at the execution table, what is the state of containers after step 3?

A Containers are removed

B Containers are stopped

C Containers are running

D Containers are created but not running

💡 Hint

Check the 'Result' and 'State Change' columns at step 3 in the execution table

At which step do containers get removed?

A Step 4

B Step 6

C Step 2

D Step 1

💡 Hint

Look for the action 'Removes containers' in the execution table

If you want volumes to be removed with 'docker compose down', what should you do?

A Add the --volumes flag to the down command

B Nothing, volumes are removed by default

C Run 'docker compose up' again

D Manually delete volumes after down

💡 Hint

Refer to the key moment about volume removal and the variable_tracker row for Volumes

Concept Snapshot

docker compose up: Reads config, creates, and starts containers
Containers run and logs show

docker compose down: Stops and removes containers
Removes networks and optionally volumes
Use --volumes flag to remove volumes
Simple way to start and clean multi-container apps

Full Transcript

Docker Compose uses a file called docker-compose.yml to define containers. When you run 'docker compose up', Docker reads this file, creates the containers, and starts them. You will see logs from the containers as they run. The containers keep running until you stop them. To stop and clean up, you run 'docker compose down'. This command stops the containers, removes them, and cleans up networks and optionally volumes if you add the --volumes flag. This process helps manage multi-container applications easily by starting and stopping all parts together.

Practice

1. What does the command docker compose up do in a multi-container application?

easy

A. Deletes the docker-compose file

B. Stops and removes all containers

C. Starts all the containers defined in the docker-compose file

D. Builds images but does not start containers

Solution

1. Step 1: Understand the purpose of docker compose up

   This command reads the docker-compose.yml file and starts all the containers defined in it.

2. Step 2: Compare with other commands

   docker compose down stops and removes containers, so it is not the same as up.

3. Final Answer:

   Starts all the containers defined in the docker-compose file -> Option C

4. Quick Check:

   docker compose up = start containers [OK]

Hint: Remember: 'up' means start containers [OK]

Common Mistakes:

• Confusing 'up' with 'down'
• Thinking 'up' deletes files
• Assuming 'up' only builds images

2. Which of the following is the correct command to stop and remove all containers started by docker compose?

easy

A. docker compose stop

B. docker compose down

C. docker compose remove

D. docker compose kill

Solution

1. Step 1: Identify the command to stop and remove containers

   docker compose down stops and removes containers, networks, and default volumes created by up.

2. Step 2: Differentiate from other commands

   docker compose stop only stops containers but does not remove them. remove is not a valid command here.

3. Final Answer:

   docker compose down -> Option B

4. Quick Check:

   down = stop and remove [OK]

Hint: Use 'down' to stop and clean containers [OK]

Common Mistakes:

• Using 'stop' which doesn't remove containers
• Trying non-existent commands like 'remove'
• Confusing 'kill' with 'down'

3. Given this sequence of commands:
docker compose up -d
docker compose down
What will be the state of the containers after these commands?

medium

A. Containers are removed and not running

B. Containers are stopped but still exist

C. Containers are running in detached mode

D. Containers are paused

Solution

1. Step 1: Analyze docker compose up -d

   This starts containers in detached mode (running in background).

2. Step 2: Analyze docker compose down

   This stops and removes all containers started by up.

3. Final Answer:

   Containers are removed and not running -> Option A

4. Quick Check:

   up -d starts, down removes [OK]

Hint: 'down' removes containers even if started detached [OK]

Common Mistakes:

• Thinking containers remain stopped but not removed
• Confusing paused with stopped
• Assuming detached means containers stay after down

4. You ran docker compose down but your containers are still running. What is the most likely reason?

medium

A. You ran docker compose down in a different directory than the compose file

B. You forgot to add -d flag

C. The containers were started with docker run instead

D. Docker daemon is not running

Solution

1. Step 1: Understand how docker compose down works

   This command affects containers defined in the compose file in the current directory.

2. Step 2: Identify why containers remain running

   If run in a different directory, it won't find or stop those containers.

3. Final Answer:

   You ran docker compose down in a different directory than the compose file -> Option A

4. Quick Check:

   Correct directory needed for down [OK]

Hint: Run commands where your compose file is located [OK]

Common Mistakes:

• Thinking -d flag affects stopping containers
• Assuming down stops containers from docker run
• Not checking Docker daemon status

5. You want to restart your multi-container app with fresh containers, removing old volumes and networks. Which command should you run?

hard

A. docker compose up --build

B. docker compose stop && docker compose start

C. docker compose restart

D. docker compose down -v && docker compose up -d

Solution

1. Step 1: Understand the need to remove old volumes and networks

   Removing volumes requires the -v flag with docker compose down.

2. Step 2: Combine commands to remove and start fresh

   docker compose down -v removes containers, networks, and volumes; docker compose up -d starts fresh containers in detached mode.

3. Final Answer:

   docker compose down -v && docker compose up -d -> Option D

4. Quick Check:

   Use down -v to remove volumes before up [OK]

Hint: Use 'down -v' to remove volumes before 'up' [OK]

Common Mistakes:

• Using 'restart' which doesn't remove volumes
• Using 'stop' and 'start' which keep old volumes
• Assuming '--build' removes volumes