:title: Command Line Interface
:description: Docker's CLI command description and usage
:keywords: Docker, Docker documentation, CLI, command line
.. _cli:
Command Line
============
To list available commands, either run ``docker`` with no parameters or execute
``docker help``::
$ sudo docker
Usage: docker [OPTIONS] COMMAND [arg...]
-H, --host=[]: The socket(s) to bind to in daemon mode, specified using one or more tcp://host:port, unix:///path/to/socket, fd://* or fd://socketfd.
A self-sufficient runtime for linux containers.
...
.. _cli_options:
Option types
------------
Single character commandline options can be combined, so rather than typing
``docker run -t -i --name test busybox sh``, you can write
``docker run -ti --name test busybox sh``.
Boolean
~~~~~~~
Boolean options look like ``-d=false``. The value you see is the
default value which gets set if you do **not** use the boolean
flag. If you do call ``run -d``, that sets the opposite boolean value,
so in this case, ``true``, and so ``docker run -d`` **will** run in
"detached" mode, in the background. Other boolean options are similar
-- specifying them will set the value to the opposite of the default
value.
Multi
~~~~~
Options like ``-a=[]`` indicate they can be specified multiple times::
docker run -a stdin -a stdout -a stderr -i -t ubuntu /bin/bash
Sometimes this can use a more complex value string, as for ``-v``::
docker run -v /host:/container example/mysql
Strings and Integers
~~~~~~~~~~~~~~~~~~~~
Options like ``--name=""`` expect a string, and they can only be
specified once. Options like ``-c=0`` expect an integer, and they can
only be specified once.
.. _cli_daemon:
``daemon``
----------
::
Usage of docker:
-D, --debug=false: Enable debug mode
-G, --group="docker": Group to assign the unix socket specified by -H when running in daemon mode; use '' (the empty string) to disable setting of a group
-H, --host=[]: The socket(s) to bind to in daemon mode, specified using one or more tcp://host:port, unix:///path/to/socket, fd://* or fd://socketfd.
--api-enable-cors=false: Enable CORS headers in the remote API
-b, --bridge="": Attach containers to a pre-existing network bridge; use 'none' to disable container networking
-bip="": Use this CIDR notation address for the network bridge's IP, not compatible with -b
-d, --daemon=false: Enable daemon mode
--dns=[]: Force docker to use specific DNS servers
--dns-search=[]: Force Docker to use specific DNS search domains
-g, --graph="/var/lib/docker": Path to use as the root of the docker runtime
--icc=true: Enable inter-container communication
--ip="0.0.0.0": Default IP address to use when binding container ports
--ip-forward=true: Enable net.ipv4.ip_forward
--iptables=true: Enable Docker's addition of iptables rules
-p, --pidfile="/var/run/docker.pid": Path to use for daemon PID file
-r, --restart=true: Restart previously running containers
-s, --storage-driver="": Force the docker runtime to use a specific storage driver
-e, --exec-driver="native": Force the docker runtime to use a specific exec driver
-v, --version=false: Print version information and quit
--tls=false: Use TLS; implied by tls-verify flags
--tlscacert="~/.docker/ca.pem": Trust only remotes providing a certificate signed by the CA given here
--tlscert="~/.docker/cert.pem": Path to TLS certificate file
--tlskey="~/.docker/key.pem": Path to TLS key file
--tlsverify=false: Use TLS and verify the remote (daemon: verify client, client: verify daemon)
--mtu=0: Set the containers network MTU; if no value is provided: default to the default route MTU or 1500 if no default route is available
Options with [] may be specified multiple times.
The Docker daemon is the persistent process that manages containers. Docker uses the same binary for both the
daemon and client. To run the daemon you provide the ``-d`` flag.
To force Docker to use devicemapper as the storage driver, use ``docker -d -s devicemapper``.
To set the DNS server for all Docker containers, use ``docker -d --dns 8.8.8.8``.
To set the DNS search domain for all Docker containers, use ``docker -d --dns-search example.com``.
To run the daemon with debug output, use ``docker -d -D``.
To use lxc as the execution driver, use ``docker -d -e lxc``.
The docker client will also honor the ``DOCKER_HOST`` environment variable to set
the ``-H`` flag for the client.
::
docker -H tcp://0.0.0.0:4243 ps
# or
export DOCKER_HOST="tcp://0.0.0.0:4243"
docker ps
# both are equal
To run the daemon with `systemd socket activation <http://0pointer.de/blog/projects/socket-activation.html>`_, use ``docker -d -H fd://``.
Using ``fd://`` will work perfectly for most setups but you can also specify individual sockets too ``docker -d -H fd://3``.
If the specified socket activated files aren't found then docker will exit.
You can find examples of using systemd socket activation with docker and systemd in the `docker source tree <https://github.com/dotcloud/docker/blob/master/contrib/init/systemd/socket-activation/>`_.
Docker supports softlinks for the Docker data directory (``/var/lib/docker``) and for ``/tmp``.
TMPDIR and the data directory can be set like this:
::
TMPDIR=/mnt/disk2/tmp /usr/local/bin/docker -d -D -g /var/lib/docker -H unix:// > /var/lib/boot2docker/docker.log 2>&1
# or
export TMPDIR=/mnt/disk2/tmp
/usr/local/bin/docker -d -D -g /var/lib/docker -H unix:// > /var/lib/boot2docker/docker.log 2>&1
.. _cli_attach:
``attach``
----------
::
Usage: docker attach CONTAINER
Attach to a running container.
--no-stdin=false: Do not attach stdin
--sig-proxy=true: Proxify all received signal to the process (even in non-tty mode)
The ``attach`` command will allow you to view or interact with any
running container, detached (``-d``) or interactive (``-i``). You can
attach to the same container at the same time - screen sharing style,
or quickly view the progress of your daemonized process.
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. When you detach from the container's
process the exit code will be returned to the client.
To stop a container, use ``docker stop``.
To kill the container, use ``docker kill``.
.. _cli_attach_examples:
Examples:
~~~~~~~~~
.. code-block:: bash
$ 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
.. _cli_build:
``build``
---------
::
Usage: docker build [OPTIONS] PATH | URL | -
Build a new container image from the source code at PATH
-t, --tag="": Repository name (and optionally a tag) to be applied
to the resulting image in case of success.
-q, --quiet=false: Suppress the verbose output generated by the containers.
--no-cache: Do not use the cache when building the image.
--rm=true: Remove intermediate containers after a successful build
Use this command to build Docker images from a ``Dockerfile`` and a "context".
The files at ``PATH`` or ``URL`` are called the "context" of the build.
The build process may refer to any of the files in the context, for example when
using an :ref:`ADD <dockerfile_add>` instruction.
When a single ``Dockerfile`` is given as ``URL``, then no context is set.
When a Git repository is set as ``URL``, then the repository is used as the context.
The Git repository is cloned with its submodules (`git clone --recursive`).
A fresh git clone occurs in a temporary directory on your local host, and then this
is sent to the Docker daemon as the context.
This way, your local user credentials and vpn's etc can be used to access private repositories
.. _cli_build_examples:
.. seealso:: :ref:`dockerbuilder`.
Examples:
~~~~~~~~~
.. code-block:: bash
$ sudo docker build .
Uploading context 10240 bytes
Step 1 : FROM busybox
Pulling repository busybox
---> e9aa60c60128MB/2.284 MB (100%) endpoint: https://cdn-registry-1.docker.io/v1/
Step 2 : RUN ls -lh /
---> Running in 9c9e81692ae9
total 24
drwxr-xr-x 2 root root 4.0K Mar 12 2013 bin
drwxr-xr-x 5 root root 4.0K Oct 19 00:19 dev
drwxr-xr-x 2 root root 4.0K Oct 19 00:19 etc
drwxr-xr-x 2 root root 4.0K Nov 15 23:34 lib
lrwxrwxrwx 1 root root 3 Mar 12 2013 lib64 -> lib
dr-xr-xr-x 116 root root 0 Nov 15 23:34 proc
lrwxrwxrwx 1 root root 3 Mar 12 2013 sbin -> bin
dr-xr-xr-x 13 root root 0 Nov 15 23:34 sys
drwxr-xr-x 2 root root 4.0K Mar 12 2013 tmp
drwxr-xr-x 2 root root 4.0K Nov 15 23:34 usr
---> b35f4035db3f
Step 3 : CMD echo Hello World
---> Running in 02071fceb21b
---> f52f38b7823e
Successfully built f52f38b7823e
Removing intermediate container 9c9e81692ae9
Removing intermediate container 02071fceb21b
This example specifies that the ``PATH`` is ``.``, and so all the files in
the local directory get tar'd and sent to the Docker daemon. The ``PATH``
specifies where to find the files for the "context" of the build on
the Docker daemon. Remember that the daemon could be running on a
remote machine and that no parsing of the ``Dockerfile`` happens at the
client side (where you're running ``docker build``). That means that
*all* the files at ``PATH`` get sent, not just the ones listed to
:ref:`ADD <dockerfile_add>` in the ``Dockerfile``.
The transfer of context from the local machine to the Docker daemon is
what the ``docker`` client means when you see the "Uploading context"
message.
If you wish to keep the intermediate containers after the build is complete,
you must use ``--rm=false``. This does not affect the build cache.
.. code-block:: bash
$ 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``
.. code-block:: bash
$ 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. Since there is no context, a ``Dockerfile``
``ADD`` only works if it refers to a remote URL.
.. code-block:: bash
$ sudo docker build github.com/creack/docker-firefox
This will clone the GitHub repository and use the cloned repository 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.
.. _cli_commit:
``commit``
----------
::
Usage: docker commit [OPTIONS] CONTAINER [REPOSITORY[:TAG]]
Create a new image from a container's changes
-m, --message="": Commit message
-a, --author="": Author (eg. "John Hannibal Smith <hannibal@a-team.com>"
It can be useful to commit a container's file changes or settings into a new image.
This allows you debug a container by running an interactive shell, or to export
a working dataset to another server.
Generally, it is better to use Dockerfiles to manage your images in a documented
and maintainable way.
.. _cli_commit_examples:
Commit an existing container
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. code-block:: bash
$ sudo 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 VIRTUAL SIZE
SvenDowideit/testimage version3 f5283438590d 16 seconds ago 335.7 MB
.. _cli_cp:
``cp``
------
::
Usage: docker cp CONTAINER:PATH HOSTPATH
Copy files/folders from the containers filesystem to the host
path. Paths are relative to the root of the filesystem.
.. code-block:: bash
$ sudo docker cp 7bb0e258aefe:/etc/debian_version .
$ sudo docker cp blue_frog:/etc/hosts .
.. _cli_diff:
``diff``
--------
::
Usage: docker diff CONTAINER
List the changed files and directories in a container's filesystem
There are 3 events that are listed in the 'diff':
1. ```A``` - Add
2. ```D``` - Delete
3. ```C``` - Change
For example:
.. code-block:: bash
$ sudo docker diff 7bb0e258aefe
C /dev
A /dev/kmsg
C /etc
A /etc/mtab
A /go
A /go/src
A /go/src/github.com
A /go/src/github.com/dotcloud
A /go/src/github.com/dotcloud/docker
A /go/src/github.com/dotcloud/docker/.git
....
.. _cli_events:
``events``
----------
::
Usage: docker events
Get real time events from the server
--since="": Show all events created since timestamp
(either seconds since epoch, or date string as below)
--until="": Show events created before timestamp
(either seconds since epoch, or date string as below)
.. _cli_events_example:
Examples
~~~~~~~~
You'll need two shells for this example.
Shell 1: Listening for events
.............................
.. code-block:: bash
$ sudo docker events
Shell 2: Start and Stop a Container
...................................
.. code-block:: bash
$ sudo docker start 4386fb97867d
$ sudo docker stop 4386fb97867d
Shell 1: (Again .. now showing events)
......................................
.. code-block:: bash
[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
Show events in the past from a specified time
.............................................
.. code-block:: bash
$ sudo docker events --since 1378216169
[2013-09-03 15:49:29 +0200 CEST] 4386fb97867d: (from 12de384bfb10) die
[2013-09-03 15:49:29 +0200 CEST] 4386fb97867d: (from 12de384bfb10) stop
$ sudo docker events --since '2013-09-03'
[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
$ sudo docker events --since '2013-09-03 15:49:29 +0200 CEST'
[2013-09-03 15:49:29 +0200 CEST] 4386fb97867d: (from 12de384bfb10) die
[2013-09-03 15:49:29 +0200 CEST] 4386fb97867d: (from 12de384bfb10) stop
.. _cli_export:
``export``
----------
::
Usage: docker export CONTAINER
Export the contents of a filesystem as a tar archive to STDOUT
For example:
.. code-block:: bash
$ sudo docker export red_panda > latest.tar
.. _cli_history:
``history``
-----------
::
Usage: docker history [OPTIONS] IMAGE
Show the history of an image
--no-trunc=false: Don't truncate output
-q, --quiet=false: Only show numeric IDs
To see how the ``docker:latest`` image was built:
.. code-block:: bash
$ docker history docker
IMAGE CREATED CREATED BY SIZE
3e23a5875458790b7a806f95f7ec0d0b2a5c1659bfc899c89f939f6d5b8f7094 8 days ago /bin/sh -c #(nop) ENV LC_ALL=C.UTF-8 0 B
8578938dd17054dce7993d21de79e96a037400e8d28e15e7290fea4f65128a36 8 days ago /bin/sh -c dpkg-reconfigure locales && locale-gen C.UTF-8 && /usr/sbin/update-locale LANG=C.UTF-8 1.245 MB
be51b77efb42f67a5e96437b3e102f81e0a1399038f77bf28cea0ed23a65cf60 8 days ago /bin/sh -c apt-get update && apt-get install -y git libxml2-dev python build-essential make gcc python-dev locales python-pip 338.3 MB
4b137612be55ca69776c7f30c2d2dd0aa2e7d72059820abf3e25b629f887a084 6 weeks ago /bin/sh -c #(nop) ADD jessie.tar.xz in / 121 MB
750d58736b4b6cc0f9a9abe8f258cef269e3e9dceced1146503522be9f985ada 6 weeks ago /bin/sh -c #(nop) MAINTAINER Tianon Gravi <admwiggin@gmail.com> - mkimage-debootstrap.sh -t jessie.tar.xz jessie http://http.debian.net/debian 0 B
511136ea3c5a64f264b78b5433614aec563103b4d4702f3ba7d4d2698e22c158 9 months ago 0 B
.. _cli_images:
``images``
----------
::
Usage: docker images [OPTIONS] [NAME]
List images
-a, --all=false: Show all images (by default filter out the intermediate image layers)
--no-trunc=false: Don't truncate output
-q, --quiet=false: Only show numeric IDs
The default ``docker images`` will show all top level images, their repository
and tags, and their virtual size.
Docker images have intermediate layers that increase reuseability, decrease
disk usage, and speed up ``docker build`` by allowing each step to be cached.
These intermediate layers are not shown by default.
Listing the most recently created images
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. code-block:: bash
$ sudo docker images | head
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
<none> <none> 77af4d6b9913 19 hours ago 1.089 GB
committest latest b6fa739cedf5 19 hours ago 1.089 GB
<none> <none> 78a85c484f71 19 hours ago 1.089 GB
docker latest 30557a29d5ab 20 hours ago 1.089 GB
<none> <none> 0124422dd9f9 20 hours ago 1.089 GB
<none> <none> 18ad6fad3402 22 hours ago 1.082 GB
<none> <none> f9f1e26352f0 23 hours ago 1.089 GB
tryout latest 2629d1fa0b81 23 hours ago 131.5 MB
<none> <none> 5ed6274db6ce 24 hours ago 1.089 GB
Listing the full length image IDs
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. code-block:: bash
$ sudo docker images --no-trunc | head
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
<none> <none> 77af4d6b9913e693e8d0b4b294fa62ade6054e6b2f1ffb617ac955dd63fb0182 19 hours ago 1.089 GB
committest latest b6fa739cedf5ea12a620a439402b6004d057da800f91c7524b5086a5e4749c9f 19 hours ago 1.089 GB
<none> <none> 78a85c484f71509adeaace20e72e941f6bdd2b25b4c75da8693efd9f61a37921 19 hours ago 1.089 GB
docker latest 30557a29d5abc51e5f1d5b472e79b7e296f595abcf19fe6b9199dbbc809c6ff4 20 hours ago 1.089 GB
<none> <none> 0124422dd9f9cf7ef15c0617cda3931ee68346455441d66ab8bdc5b05e9fdce5 20 hours ago 1.089 GB
<none> <none> 18ad6fad340262ac2a636efd98a6d1f0ea775ae3d45240d3418466495a19a81b 22 hours ago 1.082 GB
<none> <none> f9f1e26352f0a3ba6a0ff68167559f64f3e21ff7ada60366e2d44a04befd1d3a 23 hours ago 1.089 GB
tryout latest 2629d1fa0b81b222fca63371ca16cbf6a0772d07759ff80e8d1369b926940074 23 hours ago 131.5 MB
<none> <none> 5ed6274db6ceb2397844896966ea239290555e74ef307030ebb01ff91b1914df 24 hours ago 1.089 GB
.. _cli_import:
``import``
----------
::
Usage: docker import URL|- [REPOSITORY[:TAG]]
Create an empty filesystem image and import the contents of the tarball
(.tar, .tar.gz, .tgz, .bzip, .tar.xz, .txz) into it, then optionally tag it.
URLs must start with ``http`` and point to a single
file archive (.tar, .tar.gz, .tgz, .bzip, .tar.xz, or .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 *stdin*.
Examples
~~~~~~~~
Import from a remote location
.............................
This will create a new untagged image.
.. code-block:: bash
$ sudo docker import http://example.com/exampleimage.tgz
Import from a local file
........................
Import to docker via pipe and *stdin*.
.. code-block:: bash
$ cat exampleimage.tgz | sudo docker import - exampleimagelocal:new
Import from a local directory
.............................
.. code-block:: bash
$ 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 the sudo command) when you tar, then the ownerships might not get
preserved.
.. _cli_info:
``info``
--------
::
Usage: docker info
Display system-wide information.
.. code-block:: bash
$ sudo docker info
Containers: 292
Images: 194
Debug mode (server): false
Debug mode (client): false
Fds: 22
Goroutines: 67
LXC Version: 0.9.0
EventsListeners: 115
Kernel Version: 3.8.0-33-generic
WARNING: No swap limit support
When sending issue reports, please use ``docker version`` and ``docker info`` to
ensure we know how your setup is configured.
.. _cli_inspect:
``inspect``
-----------
::
Usage: docker inspect CONTAINER|IMAGE [CONTAINER|IMAGE...]
Return low-level information on a container/image
-f, --format="": Format the output using the given go template.
By default, this will render all results in a JSON array. If a format
is specified, the given template will be executed for each result.
Go's `text/template <http://golang.org/pkg/text/template/>`_ package
describes all the details of the format.
Examples
~~~~~~~~
Get an instance's IP Address
............................
For the most part, you can pick out any field from the JSON in a
fairly straightforward manner.
.. code-block:: bash
$ sudo docker inspect --format='{{.NetworkSettings.IPAddress}}' $INSTANCE_ID
List All Port Bindings
......................
One can loop over arrays and maps in the results to produce simple
text output:
.. code-block:: bash
$ sudo docker inspect --format='{{range $p, $conf := .NetworkSettings.Ports}} {{$p}} -> {{(index $conf 0).HostPort}} {{end}}' $INSTANCE_ID
Find a Specific Port Mapping
............................
The ``.Field`` syntax doesn't work when the field name begins with a
number, but the template language's ``index`` function does. The
``.NetworkSettings.Ports`` section contains a map of the internal port
mappings to a list of external address/port objects, so to grab just
the numeric public port, you use ``index`` to find the specific port
map, and then ``index`` 0 contains first object inside of that. Then
we ask for the ``HostPort`` field to get the public address.
.. code-block:: bash
$ sudo docker inspect --format='{{(index (index .NetworkSettings.Ports "8787/tcp") 0).HostPort}}' $INSTANCE_ID
Get config
..........
The ``.Field`` syntax doesn't work when the field contains JSON data,
but the template language's custom ``json`` function does. The ``.config``
section contains complex json object, so to grab it as JSON, you use ``json``
to convert config object into JSON
.. code-block:: bash
$ sudo docker inspect --format='{{json .config}}' $INSTANCE_ID
.. _cli_kill:
``kill``
--------
::
Usage: docker kill [OPTIONS] CONTAINER [CONTAINER...]
Kill a running container (send SIGKILL, or specified signal)
-s, --signal="KILL": Signal to send to the container
The main process inside the container will be sent SIGKILL, or any signal specified with option ``--signal``.
Known Issues (kill)
~~~~~~~~~~~~~~~~~~~
* :issue:`197` indicates that ``docker kill`` may leave directories
behind and make it difficult to remove the container.
* :issue:`3844` lxc 1.0.0 beta3 removed ``lcx-kill`` which is used by Docker versions before 0.8.0;
see the issue for a workaround.
.. _cli_load:
``load``
--------
::
Usage: docker load
Load an image from a tar archive on STDIN
-i, --input="": Read from a tar archive file, instead of STDIN
Loads a tarred repository from a file or the standard input stream.
Restores both images and tags.
.. code-block:: bash
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
$ sudo docker load < busybox.tar
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
busybox latest 769b9341d937 7 weeks ago 2.489 MB
$ sudo docker load --input fedora.tar
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
busybox latest 769b9341d937 7 weeks ago 2.489 MB
fedora rawhide 0d20aec6529d 7 weeks ago 387 MB
fedora 20 58394af37342 7 weeks ago 385.5 MB
fedora heisenbug 58394af37342 7 weeks ago 385.5 MB
fedora latest 58394af37342 7 weeks ago 385.5 MB
.. _cli_login:
``login``
---------
::
Usage: docker login [OPTIONS] [SERVER]
Register or Login to the docker registry server
-e, --email="": Email
-p, --password="": Password
-u, --username="": Username
If you want to login to a private registry you can
specify this by adding the server name.
example:
docker login localhost:8080
.. _cli_logs:
``logs``
--------
::
Usage: docker logs [OPTIONS] CONTAINER
Fetch the logs of a container
-f, --follow=false: Follow log output
The ``docker logs`` command batch-retrieves all logs present at the time of execution.
The ``docker logs --follow`` command combines ``docker logs`` and ``docker attach``:
it will first return all logs from the beginning and then continue streaming
new output from the container's stdout and stderr.
.. _cli_port:
``port``
--------
::
Usage: docker port [OPTIONS] CONTAINER PRIVATE_PORT
Lookup the public-facing port which is NAT-ed to PRIVATE_PORT
.. _cli_ps:
``ps``
------
::
Usage: docker ps [OPTIONS]
List containers
-a, --all=false: Show all containers. Only running containers are shown by default.
--before="": Show only container created before Id or Name, include non-running ones.
-l, --latest=false: Show only the latest created container, include non-running ones.
-n=-1: Show n last created containers, include non-running ones.
--no-trunc=false: Don't truncate output
-q, --quiet=false: Only display numeric IDs
-s, --size=false: Display sizes, not to be used with -q
--since="": Show only containers created since Id or Name, include non-running ones.
Running ``docker ps`` showing 2 linked containers.
.. code-block:: bash
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4c01db0b339c ubuntu:12.04 bash 17 seconds ago Up 16 seconds webapp
d7886598dbe2 crosbymichael/redis:latest /redis-server --dir 33 minutes ago Up 33 minutes 6379/tcp redis,webapp/db
``docker ps`` will show only running containers by default. To see all containers: ``docker ps -a``
.. _cli_pull:
``pull``
--------
::
Usage: docker pull NAME[:TAG]
Pull an image or a repository from the registry
Most of your images will be created on top of a base image from the
<Docker Index>(https://index.docker.io).
The Docker Index contains many pre-built images that you can ``pull`` and try
without needing to define and configure your own.
To download a particular image, or set of images (i.e., a repository),
use ``docker pull``:
.. code-block:: bash
$ docker pull debian
# will pull all the images in the debian repository
$ docker pull debian:testing
# will pull only the image named debian:testing and any intermediate layers
# it is based on. (typically the empty `scratch` image, a MAINTAINERs layer,
# and the un-tared base.
.. _cli_push:
``push``
--------
::
Usage: docker push NAME[:TAG]
Push an image or a repository to the registry
Use ``docker push`` to share your images on public or private registries.
.. _cli_restart:
``restart``
-----------
::
Usage: docker restart [OPTIONS] NAME
Restart a running container
-t, --time=10: Number of seconds to try to stop for before killing the container. Once killed it will then be restarted. Default=10
.. _cli_rm:
``rm``
------
::
Usage: docker rm [OPTIONS] CONTAINER
Remove one or more containers
-l, --link="": Remove the link instead of the actual container
-f, --force=false: Force removal of running container
-v, --volumes=false: Remove the volumes associated to the container
Known Issues (rm)
~~~~~~~~~~~~~~~~~
* :issue:`197` indicates that ``docker kill`` may leave directories
behind and make it difficult to remove the container.
Examples:
~~~~~~~~~
.. code-block:: bash
$ sudo docker rm /redis
/redis
This will remove the container referenced under the link ``/redis``.
.. code-block:: bash
$ sudo docker rm --link /webapp/redis
/webapp/redis
This will remove the underlying link between ``/webapp`` and the ``/redis`` containers removing all
network communication.
.. code-block:: bash
$ sudo docker rm $(docker ps -a -q)
This command will delete all stopped containers. The command ``docker ps -a -q`` will return all
existing container IDs and pass them to the ``rm`` command which will delete them. Any running
containers will not be deleted.
.. _cli_rmi:
``rmi``
-------
::
Usage: docker rmi IMAGE [IMAGE...]
Remove one or more images
-f, --force=false: Force
--no-prune=false: Do not delete untagged parents
Removing tagged images
~~~~~~~~~~~~~~~~~~~~~~
Images can be removed either by their short or long ID's, or their image names.
If an image has more than one name, each of them needs to be removed before the
image is removed.
.. code-block:: bash
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
test1 latest fd484f19954f 23 seconds ago 7 B (virtual 4.964 MB)
test latest fd484f19954f 23 seconds ago 7 B (virtual 4.964 MB)
test2 latest fd484f19954f 23 seconds ago 7 B (virtual 4.964 MB)
$ sudo docker rmi fd484f19954f
Error: Conflict, cannot delete image fd484f19954f because it is tagged in multiple repositories
2013/12/11 05:47:16 Error: failed to remove one or more images
$ sudo docker rmi test1
Untagged: fd484f19954f4920da7ff372b5067f5b7ddb2fd3830cecd17b96ea9e286ba5b8
$ sudo docker rmi test2
Untagged: fd484f19954f4920da7ff372b5067f5b7ddb2fd3830cecd17b96ea9e286ba5b8
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
test1 latest fd484f19954f 23 seconds ago 7 B (virtual 4.964 MB)
$ sudo docker rmi test
Untagged: fd484f19954f4920da7ff372b5067f5b7ddb2fd3830cecd17b96ea9e286ba5b8
Deleted: fd484f19954f4920da7ff372b5067f5b7ddb2fd3830cecd17b96ea9e286ba5b8
.. _cli_run:
``run``
-------
::
Usage: docker run [OPTIONS] IMAGE[:TAG] [COMMAND] [ARG...]
Run a command in a new container
-a, --attach=map[]: Attach to stdin, stdout or stderr
-c, --cpu-shares=0: CPU shares (relative weight)
--cidfile="": Write the container ID to the file
-d, --detach=false: Detached mode: Run container in the background, print new container id
-e, --env=[]: Set environment variables
--env-file="": Read in a line delimited file of ENV variables
-h, --hostname="": Container host name
-i, --interactive=false: Keep stdin open even if not attached
--privileged=false: Give extended privileges to this container
-m, --memory="": Memory limit (format: <number><optional unit>, where unit = b, k, m or g)
-n, --networking=true: Enable networking for this container
-p, --publish=[]: Map a network port to the container
--rm=false: Automatically remove the container when it exits (incompatible with -d)
-t, --tty=false: Allocate a pseudo-tty
-u, --user="": Username or UID
--dns=[]: Set custom dns servers for the container
--dns-search=[]: Set custom DNS search domains for the container
-v, --volume=[]: Create a bind mount to a directory or file with: [host-path]:[container-path]:[rw|ro]. If a directory "container-path" is missing, then docker creates a new volume.
--volumes-from="": Mount all volumes from the given container(s)
--entrypoint="": Overwrite the default entrypoint set by the image
-w, --workdir="": Working directory inside the container
--lxc-conf=[]: (lxc exec-driver only) 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, --publish-all=false: Publish all exposed ports to the host interfaces
The ``docker run`` command first ``creates`` a writeable container layer over
the specified image, and then ``starts`` it using the specified command. That
is, ``docker run`` is equivalent to the API ``/containers/create`` then
``/containers/(id)/start``.
A stopped container can be restarted with all its previous changes intact using
``docker start``. See ``docker ps -a`` to view a list of all containers.
The ``docker run`` command can be used in combination with ``docker commit`` to
:ref:`change the command that a container runs <cli_commit_examples>`.
See :ref:`port_redirection` for more detailed information about the ``--expose``,
``-p``, ``-P`` and ``--link`` parameters, and :ref:`working_with_links_names` for
specific examples using ``--link``.
Known Issues (run --volumes-from)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* :issue:`2702`: "lxc-start: Permission denied - failed to mount"
could indicate a permissions problem with AppArmor. Please see the
issue for a workaround.
Examples:
~~~~~~~~~
.. code-block:: bash
$ 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.
.. code-block:: bash
$ sudo docker run -t -i --rm ubuntu bash
root@bc338942ef20:/# mount -t tmpfs none /mnt
mount: permission denied
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:
.. code-block:: bash
$ sudo docker run --privileged ubuntu bash
root@50e3f57e16e6:/# mount -t tmpfs none /mnt
root@50e3f57e16e6:/# df -h
Filesystem Size Used Avail Use% Mounted on
none 1.9G 0 1.9G 0% /mnt
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.
.. code-block:: bash
$ sudo 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.
.. code-block:: bash
$ sudo 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.
.. code-block:: bash
$ sudo docker run -v /doesnt/exist:/foo -w /foo -i -t ubuntu bash
When the host directory of a bind-mounted volume doesn't exist, Docker
will automatically create this directory on the host for you. In the
example above, Docker will create the ``/doesnt/exist`` folder before
starting your container.
.. code-block:: bash
$ sudo docker run -t -i -v /var/run/docker.sock:/var/run/docker.sock -v ./static-docker:/usr/bin/docker busybox sh
By bind-mounting the docker unix socket and statically linked docker binary
(such as that provided by https://get.docker.io), you give the container
the full access to create and manipulate the host's docker daemon.
.. code-block:: bash
$ sudo 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. :ref:`port_redirection` explains in detail how to manipulate ports
in Docker.
.. code-block:: bash
$ sudo 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. :ref:`port_redirection`
explains in detail how to manipulate ports in Docker.
.. code-block:: bash
$ sudo docker run -e MYVAR1 --env MYVAR2=foo --env-file ./env.list ubuntu bash
This sets environmental variables in the container. For illustration all three
flags are shown here. Where ``-e``, ``--env`` take an environment variable and
value, or if no "=" is provided, then that variable's current value is passed
through (i.e. $MYVAR1 from the host is set to $MYVAR1 in the container). All
three flags, ``-e``, ``--env`` and ``--env-file`` can be repeated.
Regardless of the order of these three flags, the ``--env-file`` are processed
first, and then ``-e``/``--env`` flags. This way, the ``-e`` or ``--env`` will
override variables as needed.
.. code-block:: bash
$ cat ./env.list
TEST_FOO=BAR
$ sudo docker run --env TEST_FOO="This is a test" --env-file ./env.list busybox env | grep TEST_FOO
TEST_FOO=This is a test
The ``--env-file`` flag takes a filename as an argument and expects each line
to be in the VAR=VAL format, mimicking the argument passed to ``--env``.
Comment lines need only be prefixed with ``#``
An example of a file passed with ``--env-file``
.. code-block:: bash
$ cat ./env.list
TEST_FOO=BAR
# this is a comment
TEST_APP_DEST_HOST=10.10.0.127
TEST_APP_DEST_PORT=8888
# pass through this variable from the caller
TEST_PASSTHROUGH
$ sudo TEST_PASSTHROUGH=howdy docker run --env-file ./env.list busybox env
HOME=/
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=5198e0745561
TEST_FOO=BAR
TEST_APP_DEST_HOST=10.10.0.127
TEST_APP_DEST_PORT=8888
TEST_PASSTHROUGH=howdy
.. code-block:: bash
$ sudo docker run --name console -t -i ubuntu bash
This will create and run a new container with the container name
being ``console``.
.. code-block:: bash
$ sudo 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.
.. code-block:: bash
$ sudo docker run --volumes-from 777f7dc92da7,ba8c0c54f0f2:ro -i -t ubuntu pwd
The ``--volumes-from`` flag mounts all the defined volumes from the
referenced containers. Containers can be specified by a comma separated
list or by repetitions of the ``--volumes-from`` argument. The container
ID may be optionally suffixed with ``:ro`` or ``:rw`` to mount the volumes in
read-only or read-write mode, respectively. By default, the volumes are mounted
in the same mode (read write or read only) as the reference container.
The ``-a`` flag tells ``docker run`` to bind to the container's stdin, stdout
or stderr. This makes it possible to manipulate the output and input as needed.
.. code-block:: bash
$ sudo echo "test" | docker run -i -a stdin ubuntu cat -
This pipes data into a container and prints the container's ID by attaching
only to the container's stdin.
.. code-block:: bash
$ sudo docker run -a stderr ubuntu echo test
This isn't going to print anything unless there's an error because we've only
attached to the stderr of the container. The container's logs still store
what's been written to stderr and stdout.
.. code-block:: bash
$ sudo cat somefile | docker run -i -a stdin mybuilder dobuild
This is how piping a file into a container could be done for a build.
The container's ID will be printed after the build is done and the build logs
could be retrieved using ``docker logs``. This is useful if you need to pipe
a file or something else into a container and retrieve the container's ID once
the container has finished running.
A complete example
..................
.. code-block:: bash
$ sudo docker run -d --name static static-web-files sh
$ sudo docker run -d --expose=8098 --name riak riakserver
$ sudo docker run -d -m 100m -e DEVELOPMENT=1 -e BRANCH=example-code -v $(pwd):/app/bin:ro --name app appserver
$ sudo docker run -d -p 1443:443 --dns=dns.dev.org --dns-search=dev.org -v /var/log/httpd --volumes-from static --link riak --link app -h www.sven.dev.org --name web webserver
$ sudo docker run -t -i --rm --volumes-from web -w /var/log/httpd busybox tail -f access.log
This example shows 5 containers that might be set up to test a web application change:
1. Start a pre-prepared volume image ``static-web-files`` (in the background) that has CSS, image and static HTML in it, (with a ``VOLUME`` instruction in the ``Dockerfile`` to allow the web server to use those files);
2. Start a pre-prepared ``riakserver`` image, give the container name ``riak`` and expose port ``8098`` to any containers that link to it;
3. Start the ``appserver`` image, restricting its memory usage to 100MB, setting two environment variables ``DEVELOPMENT`` and ``BRANCH`` and bind-mounting the current directory (``$(pwd)``) in the container in read-only mode as ``/app/bin``;
4. Start the ``webserver``, mapping port ``443`` in the container to port ``1443`` on the Docker server, setting the DNS server to ``dns.dev.org`` and DNS search domain to ``dev.org``, creating a volume to put the log files into (so we can access it from another container), then importing the files from the volume exposed by the ``static`` container, and linking to all exposed ports from ``riak`` and ``app``. Lastly, we set the hostname to ``web.sven.dev.org`` so its consistent with the pre-generated SSL certificate;
5. Finally, we create a container that runs ``tail -f access.log`` using the logs volume from the ``web`` container, setting the workdir to ``/var/log/httpd``. The ``--rm`` option means that when the container exits, the container's layer is removed.
.. _cli_save:
``save``
---------
::
Usage: docker save IMAGE
Save an image to a tar archive (streamed to stdout by default)
-o, --output="": Write to an file, instead of STDOUT
Produces a tarred repository to the standard output stream.
Contains all parent layers, and all tags + versions, or specified repo:tag.
It is used to create a backup that can then be used with ``docker load``
.. code-block:: bash
$ sudo docker save busybox > busybox.tar
$ ls -sh b.tar
2.7M b.tar
$ sudo docker save --output busybox.tar busybox
$ ls -sh b.tar
2.7M b.tar
$ sudo docker save -o fedora-all.tar fedora
$ sudo docker save -o fedora-latest.tar fedora:latest
.. _cli_search:
``search``
----------
::
Usage: docker search TERM
Search the docker index for images
--no-trunc=false: Don't truncate output
-s, --stars=0: Only displays with at least xxx stars
-t, --trusted=false: Only show trusted builds
See :ref:`searching_central_index` for more details on finding shared images
from the commandline.
.. _cli_start:
``start``
---------
::
Usage: docker start [OPTIONS] CONTAINER
Start a stopped container
-a, --attach=false: Attach container᾿s stdout/stderr and forward all signals to the process
-i, --interactive=false: Attach container᾿s stdin
.. _cli_stop:
``stop``
--------
::
Usage: docker stop [OPTIONS] CONTAINER [CONTAINER...]
Stop a running container (Send SIGTERM, and then SIGKILL after grace period)
-t, --time=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
.. _cli_tag:
``tag``
-------
::
Usage: docker tag [OPTIONS] IMAGE [REGISTRYHOST/][USERNAME/]NAME[:TAG]
Tag an image into a repository
-f, --force=false: Force
You can group your images together using names and
tags, and then upload them to :ref:`working_with_the_repository`.
.. _cli_top:
``top``
-------
::
Usage: docker top CONTAINER [ps OPTIONS]
Lookup the running processes of a container
.. _cli_version:
``version``
-----------
Show the version of the Docker client, daemon, and latest released version.
.. _cli_wait:
``wait``
--------
::
Usage: docker wait [OPTIONS] NAME
Block until a container stops, then print its exit code.