NAME¶

docker - Docker image and container command line interface

SYNOPSIS¶

docker [OPTIONS] COMMAND [arg...]

DESCRIPTION¶

docker has two distinct functions. It is used for starting the Docker daemon and to run the CLI (i.e., to command the daemon to manage images, containers etc.) So docker is both a server, as a daemon, and a client to the daemon, through the CLI. To run the Docker daemon you do not specify any of the commands listed below but must specify the -d option. The other options listed below are for the daemon only. The Docker CLI has over 30 commands. The commands are listed below and each has its own man page which explain usage and arguments. To see the man page for a command run man docker .

OPTIONS¶

-h, --help
Print usage statement --api-cors-header=""
Set CORS headers in the remote API. Default is cors disabled. Give urls like " ⟨http://foo⟩, ⟨http://bar⟩, ...". Give "*" to allow all. -b, --bridge=""
Attach containers to a pre-existing network bridge; use 'none' to disable container networking --bip=""
Use the provided CIDR notation address for the dynamically created bridge (docker0); Mutually exclusive of -b -D, --debug=true|false
Enable debug mode. Default is false. -d, --daemon=true|false
Enable daemon mode. Default is false. --dns=""
Force Docker to use specific DNS servers -e, --exec-driver=""
Force Docker to use specific exec driver. Default is native. --fixed-cidr=""
IPv4 subnet for fixed IPs (e.g., 10.20.0.0/16); this subnet must be nested in the bridge subnet (which is defined by -b or --bip) --fixed-cidr-v6=""
IPv6 subnet for global IPv6 addresses (e.g., 2a00:1450::/64) -G, --group=""
Group to assign the unix socket specified by -H when running in daemon mode.
use '' (the empty string) to disable setting of a group. Default is docker. -g, --graph=""
Path to use as the root of the Docker runtime. Default is /var/lib/docker. -H, --host=[unix:///var/run/docker.sock]: tcp://[host:port] to bind or unix://[/path/to/socket] to use.
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. --icc=true|false
Allow unrestricted inter-container and Docker daemon host communication. If disabled, containers can still be linked together using --link option (see docker-run(1)). Default is true. --ip=""
Default IP address to use when binding container ports. Default is 0.0.0.0. --ip-forward=true|false
Docker will enable IP forwarding. Default is true. If --fixed-cidr-v6 is set. IPv6 forwarding will be activated, too. This may reject Router Advertisements and interfere with the host's existing IPv6 configuration. For more information please consult the documentation about "Advanced Networking - IPv6". --ip-masq=true|false
Enable IP masquerading for bridge's IP range. Default is true. --iptables=true|false
Enable Docker's addition of iptables rules. Default is true. --ipv6=true|false
Enable IPv6 support. Default is false. Docker will create an IPv6-enabled bridge with address fe80::1 which will allow you to create IPv6-enabled containers. Use together with --fixed-cidr-v6 to provide globally routable IPv6 addresses. IPv6 forwarding will be enabled if not used with --ip-forward=false. This may collide with your host's current IPv6 settings. For more information please consult the documentation about "Advanced Networking - IPv6". -l, --log-level="debug|info|warn|error| fatal""
Set the logging level. Default is info. --label="[]"
Set key=value labels to the daemon (displayed in docker info) --log-driver="json-file|syslog|none"
Container's logging driver. Default is default.
Warning: docker logs command works only for json-file logging driver. --mtu=VALUE
Set the containers network mtu. Default is 0. -p, --pidfile=""
Path to use for daemon PID file. Default is /var/run/docker.pid --registry-mirror=://
Prepend a registry mirror to be used for image pulls. May be specified multiple times. -s, --storage-driver=""
Force the Docker runtime to use a specific storage driver. --storage-opt=[]
Set storage driver options. See STORAGE DRIVER OPTIONS. -tls=true|false
Use TLS; implied by --tlsverify. Default is false. -tlsverify=true|false
Use TLS and verify the remote (daemon: verify client, client: verify daemon).
Default is false. -v, --version=true|false
Print version information and quit. Default is false. --selinux-enabled=true|false
Enable selinux support. Default is false. SELinux does not presently support the BTRFS storage driver.

COMMANDS¶

docker-attach(1)
Attach to a running container docker-build(1)
Build an image from a Dockerfile docker-commit(1)
Create a new image from a container's changes docker-cp(1)
Copy files/folders from a container's filesystem to the host docker-create(1)
Create a new container docker-diff(1)
Inspect changes on a container's filesystem docker-events(1)
Get real time events from the server docker-exec(1)
Run a command in a running container docker-export(1)
Stream the contents of a container as a tar archive docker-history(1)
Show the history of an image docker-images(1)
List images docker-import(1)
Create a new filesystem image from the contents of a tarball docker-info(1)
Display system-wide information docker-inspect(1)
Return low-level information on a container or image docker-kill(1)
Kill a running container (which includes the wrapper process and everything inside it) docker-load(1)
Load an image from a tar archive docker-login(1)
Register or login to a Docker Registry Service docker-logout(1)
Log the user out of a Docker Registry Service docker-logs(1)
Fetch the logs of a container docker-pause(1)
Pause all processes within a container docker-port(1)
Lookup the public-facing port which is NAT-ed to PRIVATE_PORT docker-ps(1)
List containers docker-pull(1)
Pull an image or a repository from a Docker Registry Service docker-push(1)
Push an image or a repository to a Docker Registry Service docker-restart(1)
Restart a running container docker-rm(1)
Remove one or more containers docker-rmi(1)
Remove one or more images docker-run(1)
Run a command in a new container docker-save(1)
Save an image to a tar archive docker-search(1)
Search for an image in the Docker index docker-start(1)
Start a stopped container docker-stats(1)
Display a live stream of one or more containers' resource usage statistics docker-stop(1)
Stop a running container docker-tag(1)
Tag an image into a repository docker-top(1)
Lookup the running processes of a container docker-unpause(1)
Unpause all processes within a container docker-version(1)
Show the Docker version information docker-wait(1)
Block until a container stops, then print its exit code

STORAGE DRIVER OPTIONS¶

Options to storage backend can be specified with --storage-opt flags. The only backend which currently takes options is devicemapper. Therefore use these flags with -s=devicemapper. Here is the list of devicemapper options:

dm.basesize¶

Specifies the size to use when creating the base device, which limits the size of images and containers. The default value is 10G. Note, thin devices are inherently "sparse", so a 10G device which is mostly empty doesn't use 10 GB of space on the pool. However, the filesystem will use more space for the empty case the larger the device is. Warning: This value affects the system-wide "base" empty filesystem that may already be initialized and inherited by pulled images.

dm.loopdatasize¶

Specifies the size to use when creating the loopback file for the "data" device which is used for the thin pool. The default size is 100G. Note that the file is sparse, so it will not initially take up this much space.

dm.loopmetadatasize¶

Specifies the size to use when creating the loopback file for the "metadadata" device which is used for the thin pool. The default size is 2G. Note that the file is sparse, so it will not initially take up this much space.

dm.fs¶

Specifies the filesystem type to use for the base device. The supported options are "ext4" and "xfs". The default is "ext4"

dm.mkfsarg¶

Specifies extra mkfs arguments to be used when creating the base device.

dm.mountopt¶

Specifies extra mount options used when mounting the thin devices.

dm.datadev¶

Specifies a custom blockdevice to use for data for the thin pool. If using a block device for device mapper storage, ideally both datadev and metadatadev should be specified to completely avoid using the loopback device.

dm.metadatadev¶

Specifies a custom blockdevice to use for metadata for the thin pool. For best performance the metadata should be on a different spindle than the data, or even better on an SSD. If setting up a new metadata pool it is required to be valid. This can be achieved by zeroing the first 4k to indicate empty metadata, like this:

dm.blocksize¶

Specifies a custom blocksize to use for the thin pool. The default blocksize is 64K.

dm.blkdiscard¶

Enables or disables the use of blkdiscard when removing devicemapper devices. This is enabled by default (only) if using loopback devices and is required to resparsify the loopback file on image/container removal. Disabling this on loopback can lead to much faster container removal times, but will prevent the space used in /var/lib/docker directory from being returned to the system for other use when containers are removed.

EXAMPLES¶

Launching docker daemon with devicemapper backend with particular block devices for data and metadata:

Client¶

For specific client examples please see the man page for the specific Docker command. For example:

HISTORY¶

April 2014, Originally compiled by William Henry (whenry at redhat dot com) based on docker.com source material and internal work.