~/everything-else/Docker reference
Updated Feb 26, 2021
🐳 Docker reference
attach Attach local standard input, output, and error streams to a running container
build Build an image from a Dockerfile
commit Create a new image from a container's changes
create Create a new container
cp Copy files/folders between a container and the local filesystem
diff Inspect changes to files or directories on a container's filesystem
export Export a container's filesystem as a tar archive
import Import the contents from a tarball to create a filesystem image
history Show the history of an image
save Save one or more images to a tar archive (streamed to STDOUT by default)
update Update configuration of one or more containers
tag Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE
load Load an image from a tar archive or STDIN
images List images
rmi Remove one or more images
exec Run a command in a running container
rm Remove one or more containers
ps List containers
run Run a command in a new container
rename Rename a container
login Log in to a Docker registry
logout Log out from a Docker registry
pull Pull an image or a repository from a registry
push Push an image or a repository to a registry
search Search the Docker Hub for images
events Get real time events from the server
top Display the running processes of a container
port List port mappings or a specific mapping for the container
stats Display a live stream of container(s) resource usage statistics
logs Fetch the logs of a container
kill Kill one or more running containers
pause Pause all processes within one or more containers
restart Restart one or more containers
unpause Unpause all processes within one or more containers
wait Block until one or more containers stop, then print their exit codes
stop Stop one or more running containers
start Start one or more stopped containers
run: create a new container
docker run -d -p X:Y <image>
-dfor detach-pto map port X of the host to port Y of the container
Interactive shell
New container:
docker run -it --entrypoint /bin/sh <image>
Existing container:
docker exec <container> /bin/sh
-ikeep stdin open-tallocate pseudo-terminal
build
docker build -t <tag> <dir or url>
Listing containers
Running: docker ps
All: docker ps -a
Stopped containers
If a container command completes, or a container is killed. The container reaches ‘stopped’ state.
Stopped containers are preserved. They can be restarted. Or the state can be committed to a new image.
docker ps -a shows all containers, including stopped ones
Removing containers
docker rm <id or name>
Remove all stopped containers
docker ps -aq -f status=exited | xargs docker rm
-a: show all-q: only list container id-f: filter
Dockerfile
Example directory layout:
Dockerfile
.dockerignore
data/
cats.csv
dogs.csv
scripts/
install.sh
run.sh
Example Dockerfile:
FROM alpine:latest
WORKDIR /app
COPY . .
RUN chmod +x scripts/*.sh
RUN scripts/install.sh
ENTRYPOINT ["/bin/sh", "scripts/run.sh"]
CMD ["default"]
FROM- Base image, requiredWORKDIR- change working directory in container (creates non-existing directories)COPY- from host to containerRUN- execute command in a new container layer and commit resultsENTRYPOINT- command to execute when runningCMD- default arguments to entrypoint
Volumes & Mounts
Named volume
Volume is a special file on the host that is mounted in containers.
# Create
docker volume create <volume_name>
# Start with mount
docker run -v <volume_name>:<mount_point> <image>
# Show details
docker volume inspect <volume_name>
Bind Mount
Mount a host directory inside the container.
docker run -v <host_dir>:<mount_point> <image>
Volume commands:
create Create a volume
inspect Display detailed information on one or more volumes
ls List volumes
prune Remove all unused local volumes
rm Remove one or more volumes
Network
Put containers on the same network to let them talk to each-other.
# Create network
docker network create <network_name>
# Start with network and network hostname
docker run --network <network_name> --network-alias <container_hostname> <image>
Example:
# Listen on host1
docker run --network testnet --network-alias host1 <image>
docker exec -it <host1 container name> nc -v -l -p 3000
# Connect from host2
docker run --network testnet --network-alias host2 <image>
docker exec -it <host2 container name> nc host1.testnet 3000
Network Commands
connect Connect a container to a network
create Create a network
disconnect Disconnect a container from a network
inspect Display detailed information on one or more networks
ls List networks
prune Remove all unused networks
rm Remove one or more networks
Docker compose
Compose containers via docker-compose.yml specification.
Network is automatically created.
version: "3.7"
services:
listener:
image: alpine:latest
command: nc -v -l -p 3000
ping:
image: alpine:latest
command: echo hello | nc listener 3000
Commands
down Stop and remove containers, networks, images, and volumes
up Create and start containers
config Validate and view the Compose file
create Create services
build Build or rebuild services
events Receive real time events from containers
logs View output from containers
exec Execute a command in a running container
kill Kill containers
rm Remove stopped containers
images List images
pull Pull service images
push Push service images
ps List containers
port Print the public port for a port binding
top Display the running processes
run Run a one-off command
scale Set number of containers for a service
start Start services
stop Stop services
restart Restart services
unpause Unpause services
pause Pause services
Debug
Image history
Trace the steps that built the image
docker image history <image>