46 KiB
page_title: Command Line Interface page_description: Docker's CLI command description and usage page_keywords: Docker, Docker documentation, CLI, command line
Command Line
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. When host=[127.0.0.1] is omitted for tcp or path=[/var/run/docker.sock] is omitted for unix sockets, default values are used.
A self-sufficient runtime for linux containers.
...
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.
daemon
Usage of docker:
-D, --debug=false: Enable debug mode
-H, --host=[]: Multiple tcp://host:port or unix://path/to/socket to bind in daemon mode, single connection otherwise. systemd socket activation can be used with fd://[socketfd].
-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
--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
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,
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.
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
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
.
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, --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
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
See also
Examples:
$ 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
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.
$ 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. Since
there is no context, a Dockerfile
ADD
only works if it refers to a remote URL.
$ 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.
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.
Commit an existing container
$ 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
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.
$ sudo docker cp 7bb0e258aefe:/etc/debian_version .
$ sudo docker cp blue_frog:/etc/hosts .
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’:
`A`
- Add`D`
- Delete`C`
- Change
For example:
$ 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
....
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)
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
Show events in the past from a specified time
$ 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
export
Usage: docker export CONTAINER
Export the contents of a filesystem as a tar archive to STDOUT
For example:
$ sudo docker export red_panda > latest.tar
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:
$ 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
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
$ 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
$ 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
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.
$ sudo docker import http://example.com/exampleimage.tgz
Import from a local file
Import to docker via pipe and stdin.
$ 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 the sudo command) when you
tar, then the ownerships might not get preserved.
info
Usage: docker info
Display system-wide information.
$ 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.
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 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.
$ 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:
$ 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.
$ 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
$ sudo docker inspect --format='{{json .config}}' $INSTANCE_ID
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.
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.
$ 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
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
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.
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, --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.
$ 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
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
:
$ 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.
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.
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
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:
$ sudo docker rm /redis
/redis
This will remove the container referenced under the link
/redis
.
$ sudo docker rm --link /webapp/redis
/webapp/redis
This will remove the underlying link between /webapp
and the /redis
containers removing all
network communication.
$ 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.
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.
$ 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
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 change the command that a
container runs.
See Redirect Ports
for more detailed information about the --expose
,
-p
, -P
and
--link
parameters, and Link
Containers
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:
$ 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.
$ 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:
$ 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.
$ 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.
$ 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.
$ 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.
$ 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.
$ 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. Redirect
Ports explains in
detail how to manipulate ports in Docker.
$ 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. Redirect
Ports explains in
detail how to manipulate ports in Docker.
$ 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.
$ 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
$ 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
$ sudo docker run --name console -t -i ubuntu bash
This will create and run a new container with the container name being
console
.
$ 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.
$ 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.
$ 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.
$ 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.
$ 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
$ 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:
- Start a pre-prepared volume image
static-web-files
(in the background) that has CSS, image and static HTML in it, (with aVOLUME
instruction in theDockerfile
to allow the web server to use those files); - Start a pre-prepared
riakserver
image, give the container nameriak
and expose port8098
to any containers that link to it; - Start the
appserver
image, restricting its memory usage to 100MB, setting two environment variablesDEVELOPMENT
andBRANCH
and bind-mounting the current directory ($(pwd)
) in the container in read-only mode as/app/bin
; - Start the
webserver
, mapping port443
in the container to port1443
on the Docker server, setting the DNS server todns.dev.org
and DNS search domain todev.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 thestatic
container, and linking to all exposed ports fromriak
andapp
. Lastly, we set the hostname toweb.sven.dev.org
so its consistent with the pre-generated SSL certificate; - Finally, we create a container that runs
tail -f access.log
using the logs volume from theweb
container, setting the workdir to/var/log/httpd
. The--rm
option means that when the container exits, the container’s layer is removed.
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
$ 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
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 Find Public Images on the Central Index for more details on finding shared images from the commandline.
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
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
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 Share Images via Repositories.
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.