cli/components/engine/docs/sources/commandline/cli.rst

title

Command Line Interface

description

Docker's CLI command description and usage

keywords

Docker, Docker documentation, CLI, command line

Command Line Help

To list available commands, either run docker with no parameters or execute docker help:

$ sudo docker
  Usage: docker [OPTIONS] COMMAND [arg...]
    -H=[unix:///var/run/docker.sock]: tcp://host:port to bind/connect to or unix://path/to/socket to use

  A self-sufficient runtime for linux containers.

  ...

attach

Usage: docker attach CONTAINER

Attach to a running container.

  -nostdin=false: Do not attach stdin
  -sig-proxy=true: Proxify all received signal to the process (even in non-tty mode)

You can detach from the container again (and leave it running) with CTRL-c (for a quiet exit) or CTRL-\ to get a stacktrace of the Docker client when it quits.

To stop a container, use docker stop

To kill the container, use docker kill

Examples:

$ ID=$(sudo docker run -d ubuntu /usr/bin/top -b)
$ sudo docker attach $ID
top - 02:05:52 up  3:05,  0 users,  load average: 0.01, 0.02, 0.05
Tasks:   1 total,   1 running,   0 sleeping,   0 stopped,   0 zombie
Cpu(s):  0.1%us,  0.2%sy,  0.0%ni, 99.7%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:    373572k total,   355560k used,    18012k free,    27872k buffers
Swap:   786428k total,        0k used,   786428k free,   221740k cached

PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
 1 root      20   0 17200 1116  912 R    0  0.3   0:00.03 top

 top - 02:05:55 up  3:05,  0 users,  load average: 0.01, 0.02, 0.05
 Tasks:   1 total,   1 running,   0 sleeping,   0 stopped,   0 zombie
 Cpu(s):  0.0%us,  0.2%sy,  0.0%ni, 99.8%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
 Mem:    373572k total,   355244k used,    18328k free,    27872k buffers
 Swap:   786428k total,        0k used,   786428k free,   221776k cached

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
   1 root      20   0 17208 1144  932 R    0  0.3   0:00.03 top


 top - 02:05:58 up  3:06,  0 users,  load average: 0.01, 0.02, 0.05
 Tasks:   1 total,   1 running,   0 sleeping,   0 stopped,   0 zombie
 Cpu(s):  0.2%us,  0.3%sy,  0.0%ni, 99.5%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
 Mem:    373572k total,   355780k used,    17792k free,    27880k buffers
 Swap:   786428k total,        0k used,   786428k free,   221776k cached

 PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
      1 root      20   0 17208 1144  932 R    0  0.3   0:00.03 top
^C$
$ sudo docker stop $ID

build

Usage: docker build [OPTIONS] PATH | URL | -
Build a new container image from the source code at PATH
  -t="": Repository name (and optionally a tag) to be applied to the resulting image in case of success.
  -q=false: Suppress verbose build output.
  -no-cache: Do not use the cache when building the image.
  -rm: Remove intermediate containers after a successful build
When a single Dockerfile is given as URL, then no context is set. When a git repository is set as URL, the repository is used as context

Examples:

sudo docker build .

This will read the Dockerfile from the current directory. It will also send any other files and directories found in the current directory to the docker daemon.

The contents of this directory would be used by ADD commands found within the Dockerfile. This will send a lot of data to the docker daemon if the current directory contains a lot of data. If the absolute path is provided instead of . then only the files and directories required by the ADD commands from the Dockerfile will be added to the context and transferred to the docker daemon.

sudo docker build -t vieux/apache:2.0 .

This will build like the previous example, but it will then tag the resulting image. The repository name will be vieux/apache and the tag will be 2.0

sudo docker build - < Dockerfile

This will read a Dockerfile from stdin without context. Due to the lack of a context, no contents of any local directory will be sent to the docker daemon. ADD doesn't work when running in this mode because the absence of the context provides no source files to copy to the container.

sudo docker build github.com/creack/docker-firefox

This will clone the Github repository and use it as context. The Dockerfile at the root of the repository is used as Dockerfile. Note that you can specify an arbitrary git repository by using the git:// schema.

commit

Usage: docker commit [OPTIONS] CONTAINER [REPOSITORY[:TAG]]

Create a new image from a container's changes

  -m="": Commit message
  -author="": Author (eg. "John Hannibal Smith <hannibal@a-team.com>"
  -run="": Configuration to be applied when the image is launched with `docker run`.
           (ex: '{"Cmd": ["cat", "/world"], "PortSpecs": ["22"]}')

Simple commit of an existing container

$ docker ps
ID                  IMAGE               COMMAND             CREATED             STATUS              PORTS
c3f279d17e0a        ubuntu:12.04        /bin/bash           7 days ago          Up 25 hours                             
197387f1b436        ubuntu:12.04        /bin/bash           7 days ago          Up 25 hours                             
$ docker commit c3f279d17e0a  SvenDowideit/testimage:version3
f5283438590d
$ docker images | head
REPOSITORY                        TAG                 ID                  CREATED             SIZE
SvenDowideit/testimage            version3            f5283438590d        16 seconds ago      204.2 MB (virtual 335.7 MB)
S

Full -run example

(multiline is ok within a single quote ')

$ sudo docker commit -run='
{
    "Entrypoint" : null,
    "Privileged" : false,
    "User" : "",
    "VolumesFrom" : "",
    "Cmd" : ["cat", "-e", "/etc/resolv.conf"],
    "Dns" : ["8.8.8.8", "8.8.4.4"],
    "MemorySwap" : 0,
    "AttachStdin" : false,
    "AttachStderr" : false,
    "CpuShares" : 0,
    "OpenStdin" : false,
    "Volumes" : null,
    "Hostname" : "122612f45831",
    "PortSpecs" : ["22", "80", "443"],
    "Image" : "b750fe79269d2ec9a3c593ef05b4332b1d1a02a62b4accb2c21d589ff2f5f2dc",
    "Tty" : false,
    "Env" : [
       "HOME=/",
       "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
    ],
    "StdinOnce" : false,
    "Domainname" : "",
    "WorkingDir" : "/",
    "NetworkDisabled" : false,
    "Memory" : 0,
    "AttachStdout" : false
}' $CONTAINER_ID

cp

Usage: docker cp CONTAINER:RESOURCE HOSTPATH

Copy files/folders from the containers filesystem to the host
path.  Paths are relative to the root of the filesystem.

diff

Usage: docker diff CONTAINER [OPTIONS]

Inspect changes on a container's filesystem

events

Usage: docker events

Get real time events from the server

Examples

You'll need two shells for this example.

Shell 1: Listening for events

$ sudo docker events

Shell 2: Start and Stop a Container

$ sudo docker start 4386fb97867d
$ sudo docker stop 4386fb97867d

Shell 1: (Again .. now showing events)

[2013-09-03 15:49:26 +0200 CEST] 4386fb97867d: (from 12de384bfb10) start
[2013-09-03 15:49:29 +0200 CEST] 4386fb97867d: (from 12de384bfb10) die
[2013-09-03 15:49:29 +0200 CEST] 4386fb97867d: (from 12de384bfb10) stop

export

Usage: docker export CONTAINER

Export the contents of a filesystem as a tar archive

history

Usage: docker history [OPTIONS] IMAGE

Show the history of an image

  -notrunc=false: Don't truncate output
  -q=false: only show numeric IDs

images

Usage: docker images [OPTIONS] [NAME]

List images

  -a=false: show all images
  -q=false: only show numeric IDs
  -viz=false: output in graphviz format

Displaying images visually

sudo docker images -viz | dot -Tpng -o docker.png

import

Usage: docker import URL|- [REPOSITORY[:TAG]]

Create a new filesystem image from the contents of a tarball

At this time, the URL must start with http and point to a single file archive (.tar, .tar.gz, .tgz, .bzip, .tar.xz, .txz) containing a root filesystem. If you would like to import from a local directory or archive, you can use the - parameter to take the data from standard in.

Examples

Import from a remote location

This will create a new untagged image.

$ sudo docker import http://example.com/exampleimage.tgz

Import from a local file

Import to docker via pipe and standard in

$ cat exampleimage.tgz | sudo docker import - exampleimagelocal:new

Import from a local directory

$ sudo tar -c . | docker import - exampleimagedir

Note the sudo in this example -- you must preserve the ownership of the files (especially root ownership) during the archiving with tar. If you are not root (or sudo) when you tar, then the ownerships might not get preserved.

info

Usage: docker info

Display system-wide information.

insert

Usage: docker insert IMAGE URL PATH

Insert a file from URL in the IMAGE at PATH

Examples

Insert file from github

$ sudo docker insert 8283e18b24bc https://raw.github.com/metalivedev/django/master/postinstall /tmp/postinstall.sh

inspect

Usage: docker inspect [OPTIONS] CONTAINER

Return low-level information on a container

kill

Usage: docker kill CONTAINER [CONTAINER...]

Kill a running container (Send SIGKILL)

The main process inside the container will be sent SIGKILL.

login

Usage: docker login [OPTIONS] [SERVER]

Register or Login to the docker registry server

-e="": email
-p="": password
-u="": username

If you want to login to a private registry you can
specify this by adding the server name.

example:
docker login localhost:8080

logs

Usage: docker logs [OPTIONS] CONTAINER

Fetch the logs of a container

port

Usage: docker port [OPTIONS] CONTAINER PRIVATE_PORT

Lookup the public-facing port which is NAT-ed to PRIVATE_PORT

ps

Usage: docker ps [OPTIONS]

List containers

  -a=false: Show all containers. Only running containers are shown by default.
  -notrunc=false: Don't truncate output
  -q=false: Only display numeric IDs

pull

Usage: docker pull NAME

Pull an image or a repository from the registry

push

Usage: docker push NAME

Push an image or a repository to the registry

restart

Usage: docker restart [OPTIONS] NAME

Restart a running container

rm

Usage: docker rm [OPTIONS] CONTAINER

Remove one or more containers
    -link="": Remove the link instead of the actual container

Examples:

$ docker rm /redis
/redis

This will remove the container referenced under the link /redis.

$ docker rm -link /webapp/redis
/webapp/redis

This will remove the underlying link between /webapp and the /redis containers removing all network communication.

rmi

Usage: docker rmi IMAGE [IMAGE...]

Remove one or more images

run

Usage: docker run [OPTIONS] IMAGE[:TAG] [COMMAND] [ARG...]

Run a command in a new container

  -a=map[]: Attach to stdin, stdout or stderr
  -c=0: CPU shares (relative weight)
  -cidfile="": Write the container ID to the file
  -d=false: Detached mode: Run container in the background, print new container id
  -e=[]: Set environment variables
  -h="": Container host name
  -i=false: Keep stdin open even if not attached
  -privileged=false: Give extended privileges to this container
  -m=0: Memory limit (in bytes)
  -n=true: Enable networking for this container
  -p=[]: Map a network port to the container
  -rm=false: Automatically remove the container when it exits (incompatible with -d)
  -t=false: Allocate a pseudo-tty
  -u="": Username or UID
  -dns=[]: Set custom dns servers for the container
  -v=[]: Create a bind mount with: [host-dir]:[container-dir]:[rw|ro]. If "container-dir" is missing, then docker creates a new volume.
  -volumes-from="": Mount all volumes from the given container
  -entrypoint="": Overwrite the default entrypoint set by the image
  -w="": Working directory inside the container
  -lxc-conf=[]: Add custom lxc options -lxc-conf="lxc.cgroup.cpuset.cpus = 0,1"
  -sig-proxy=true: Proxify all received signal to the process (even in non-tty mode)
  -expose=[]: Expose a port from the container without publishing it to your host
  -link="": Add link to another container (name:alias)
  -name="": Assign the specified name to the container. If no name is specific docker will generate a random name
  -P=false: Publish all exposed ports to the host interfaces

Examples

sudo docker run -cidfile /tmp/docker_test.cid ubuntu echo "test"

This will create a container and print "test" to the console. The cidfile flag makes docker attempt to create a new file and write the container ID to it. If the file exists already, docker will return an error. Docker will close this file when docker run exits.

docker run mount -t tmpfs none /var/spool/squid

This will not work, because by default, most potentially dangerous kernel capabilities are dropped; including cap_sys_admin (which is required to mount filesystems). However, the -privileged flag will allow it to run:

docker run -privileged mount -t tmpfs none /var/spool/squid

The -privileged flag gives all capabilities to the container, and it also lifts all the limitations enforced by the device cgroup controller. In other words, the container can then do almost everything that the host can do. This flag exists to allow special use-cases, like running Docker within Docker.

docker  run -w /path/to/dir/ -i -t  ubuntu pwd

The -w lets the command being executed inside directory given, here /path/to/dir/. If the path does not exists it is created inside the container.

docker  run  -v `pwd`:`pwd` -w `pwd` -i -t  ubuntu pwd

The -v flag mounts the current working directory into the container. The -w lets the command being executed inside the current working directory, by changing into the directory to the value returned by pwd. So this combination executes the command using the container, but inside the current working directory.

docker run -p 127.0.0.1:80:8080 ubuntu bash

This binds port 8080 of the container to port 80 on 127.0.0.1 of the host machine. port_redirection explains in detail how to manipulate ports in Docker.

docker run -expose 80 ubuntu bash

This exposes port 80 of the container for use within a link without publishing the port to the host system's interfaces. port_redirection explains in detail how to manipulate ports in Docker.

docker run -name console -t -i ubuntu bash

This will create and run a new container with the container name being console.

docker run -link /redis:redis -name console ubuntu bash

The -link flag will link the container named /redis into the newly created container with the alias redis. The new container can access the network and environment of the redis container via environment variables. The -name flag will assign the name console to the newly created container.

search

Usage: docker search TERM

Search the docker index for images

 -notrunc=false: Don't truncate output
 -stars=0: Only displays with at least xxx stars
 -trusted=false: Only show trusted builds

start

Usage: docker start [OPTIONS] NAME

Start a stopped container

  -a=false: Attach container's stdout/stderr and forward all signals to the process
  -i=false: Attach container's stdin

stop

Usage: docker stop [OPTIONS] CONTAINER [CONTAINER...]

Stop a running container (Send SIGTERM, and then SIGKILL after grace period)

  -t=10: Number of seconds to wait for the container to stop before killing it.

The main process inside the container will receive SIGTERM, and after a grace period, SIGKILL

tag

Usage: docker tag [OPTIONS] IMAGE REPOSITORY[:TAG]

Tag an image into a repository

  -f=false: Force

top

Usage: docker top CONTAINER [ps OPTIONS]

Lookup the running processes of a container

version

Show the version of the docker client, daemon, and latest released version.

wait

Usage: docker wait [OPTIONS] NAME

Block until a container stops, then print its exit code.