% DOCKER(1) Docker User Manuals % Docker Community % JUNE 2014 # NAME docker-create - Create a new container # SYNOPSIS **docker create** [**-a**|**--attach**[=*[]*]] [**--add-host**[=*[]*]] [**--blkio-weight**[=*[BLKIO-WEIGHT]*]] [**--blkio-weight-device**[=*[]*]] [**--cpu-shares**[=*0*]] [**--cap-add**[=*[]*]] [**--cap-drop**[=*[]*]] [**--cgroup-parent**[=*CGROUP-PATH*]] [**--cidfile**[=*CIDFILE*]] [**--cpu-period**[=*0*]] [**--cpu-quota**[=*0*]] [**--cpuset-cpus**[=*CPUSET-CPUS*]] [**--cpuset-mems**[=*CPUSET-MEMS*]] [**--device**[=*[]*]] [**--dns**[=*[]*]] [**--dns-search**[=*[]*]] [**--dns-opt**[=*[]*]] [**-e**|**--env**[=*[]*]] [**--entrypoint**[=*ENTRYPOINT*]] [**--env-file**[=*[]*]] [**--expose**[=*[]*]] [**--group-add**[=*[]*]] [**-h**|**--hostname**[=*HOSTNAME*]] [**--help**] [**-i**|**--interactive**[=*false*]] [**--ipc**[=*IPC*]] [**--isolation**[=*default*]] [**--kernel-memory**[=*KERNEL-MEMORY*]] [**-l**|**--label**[=*[]*]] [**--label-file**[=*[]*]] [**--link**[=*[]*]] [**--log-driver**[=*[]*]] [**--log-opt**[=*[]*]] [**-m**|**--memory**[=*MEMORY*]] [**--mac-address**[=*MAC-ADDRESS*]] [**--memory-reservation**[=*MEMORY-RESERVATION*]] [**--memory-swap**[=*MEMORY-SWAP*]] [**--memory-swappiness**[=*MEMORY-SWAPPINESS*]] [**--name**[=*NAME*]] [**--net**[=*"bridge"*]] [**--oom-kill-disable**[=*false*]] [**--oom-score-adj**[=*0*]] [**-P**|**--publish-all**[=*false*]] [**-p**|**--publish**[=*[]*]] [**--pid**[=*[]*]] [**--privileged**[=*false*]] [**--read-only**[=*false*]] [**--restart**[=*RESTART*]] [**--security-opt**[=*[]*]] [**--stop-signal**[=*SIGNAL*]] [**--shm-size**[=*[]*]] [**-t**|**--tty**[=*false*]] [**--tmpfs**[=*[CONTAINER-DIR[:]*]] [**-u**|**--user**[=*USER*]] [**--ulimit**[=*[]*]] [**--uts**[=*[]*]] [**-v**|**--volume**[=*[]*]] [**--volume-driver**[=*DRIVER*]] [**--volumes-from**[=*[]*]] [**-w**|**--workdir**[=*WORKDIR*]] IMAGE [COMMAND] [ARG...] # DESCRIPTION Creates a writeable container layer over the specified image and prepares it for running the specified command. The container ID is then printed to STDOUT. This is similar to **docker run -d** except the container is never started. You can then use the **docker start ** command to start the container at any point. The initial status of the container created with **docker create** is 'created'. # OPTIONS **-a**, **--attach**=[] Attach to STDIN, STDOUT or STDERR. **--add-host**=[] Add a custom host-to-IP mapping (host:ip) **--blkio-weight**=*0* Block IO weight (relative weight) accepts a weight value between 10 and 1000. **--blkio-weight-device**=[] Block IO weight (relative device weight, format: `DEVICE_NAME:WEIGHT`). **--cpu-shares**=*0* CPU shares (relative weight) **--cap-add**=[] Add Linux capabilities **--cap-drop**=[] Drop Linux capabilities **--cgroup-parent**="" Path to cgroups under which the cgroup for the container will be created. If the path is not absolute, the path is considered to be relative to the cgroups path of the init process. Cgroups will be created if they do not already exist. **--cidfile**="" Write the container ID to the file **--cpu-period**=*0* Limit the CPU CFS (Completely Fair Scheduler) period **--cpuset-cpus**="" CPUs in which to allow execution (0-3, 0,1) **--cpuset-mems**="" Memory nodes (MEMs) in which to allow execution (0-3, 0,1). Only effective on NUMA systems. If you have four memory nodes on your system (0-3), use `--cpuset-mems=0,1` then processes in your Docker container will only use memory from the first two memory nodes. **--cpu-quota**=*0* Limit the CPU CFS (Completely Fair Scheduler) quota **--device**=[] Add a host device to the container (e.g. --device=/dev/sdc:/dev/xvdc:rwm) **--dns**=[] Set custom DNS servers **--dns-opt**=[] Set custom DNS options **--dns-search**=[] Set custom DNS search domains (Use --dns-search=. if you don't wish to set the search domain) **-e**, **--env**=[] Set environment variables **--entrypoint**="" Overwrite the default ENTRYPOINT of the image **--env-file**=[] Read in a line-delimited file of environment variables **--expose**=[] Expose a port or a range of ports (e.g. --expose=3300-3310) from the container without publishing it to your host **--group-add**=[] Add additional groups to run as **-h**, **--hostname**="" Container host name **--help** Print usage statement **-i**, **--interactive**=*true*|*false* Keep STDIN open even if not attached. The default is *false*. **--ipc**="" Default is to create a private IPC namespace (POSIX SysV IPC) for the container 'container:': reuses another container shared memory, semaphores and message queues 'host': use the host shared memory,semaphores and message queues inside the container. Note: the host mode gives the container full access to local shared memory and is therefore considered insecure. **--isolation**="*default*" Isolation specifies the type of isolation technology used by containers. **--kernel-memory**="" Kernel memory limit (format: `[]`, where unit = b, k, m or g) Constrains the kernel memory available to a container. If a limit of 0 is specified (not using `--kernel-memory`), the container's kernel memory is not limited. If you specify a limit, it may be rounded up to a multiple of the operating system's page size and the value can be very large, millions of trillions. **-l**, **--label**=[] Adds metadata to a container (e.g., --label=com.example.key=value) **--label-file**=[] Read labels from a file. Delimit each label with an EOL. **--link**=[] Add link to another container in the form of :alias or just in which case the alias will match the name. **--log-driver**="*json-file*|*syslog*|*journald*|*gelf*|*fluentd*|*awslogs*|*splunk*|*none*" Logging driver for container. Default is defined by daemon `--log-driver` flag. **Warning**: the `docker logs` command works only for the `json-file` and `journald` logging drivers. **--log-opt**=[] Logging driver specific options. **-m**, **--memory**="" Memory limit (format: [], where unit = b, k, m or g) Allows you to constrain the memory available to a container. If the host supports swap memory, then the **-m** memory setting can be larger than physical RAM. If a limit of 0 is specified (not using **-m**), the container's memory is not limited. The actual limit may be rounded up to a multiple of the operating system's page size (the value would be very large, that's millions of trillions). **--mac-address**="" Container MAC address (e.g. 92:d0:c6:0a:29:33) **--memory-reservation**="" Memory soft limit (format: [], where unit = b, k, m or g) After setting memory reservation, when the system detects memory contention or low memory, containers are forced to restrict their consumption to their reservation. So you should always set the value below **--memory**, otherwise the hard limit will take precedence. By default, memory reservation will be the same as memory limit. **--memory-swap**="" Total memory limit (memory + swap) Set `-1` to disable swap (format: [], where unit = b, k, m or g). This value should always larger than **-m**, so you should always use this with **-m**. **--memory-swappiness**="" Tune a container's memory swappiness behavior. Accepts an integer between 0 and 100. **--name**="" Assign a name to the container **--net**="*bridge*" Set the Network mode for the container 'bridge': create a network stack on the default Docker bridge 'none': no networking 'container:': reuse another container's network stack 'host': use the Docker host network stack. Note: the host mode gives the container full access to local system services such as D-bus and is therefore considered insecure. '|': connect to a user-defined network **--oom-kill-disable**=*true*|*false* Whether to disable OOM Killer for the container or not. **--oom-score-adj**="" Tune the host's OOM preferences for containers (accepts -1000 to 1000) **-P**, **--publish-all**=*true*|*false* Publish all exposed ports to random ports on the host interfaces. The default is *false*. **-p**, **--publish**=[] Publish a container's port, or a range of ports, to the host format: ip:hostPort:containerPort | ip::containerPort | hostPort:containerPort | containerPort Both hostPort and containerPort can be specified as a range of ports. When specifying ranges for both, the number of container ports in the range must match the number of host ports in the range. (e.g., `-p 1234-1236:1234-1236/tcp`) (use 'docker port' to see the actual mapping) **--pid**=*host* Set the PID mode for the container **host**: use the host's PID namespace inside the container. Note: the host mode gives the container full access to local PID and is therefore considered insecure. **--privileged**=*true*|*false* Give extended privileges to this container. The default is *false*. **--read-only**=*true*|*false* Mount the container's root filesystem as read only. **--restart**="*no*" Restart policy to apply when a container exits (no, on-failure[:max-retry], always, unless-stopped). **--shm-size**="" Size of `/dev/shm`. The format is ``. `number` must be greater than `0`. Unit is optional and can be `b` (bytes), `k` (kilobytes), `m` (megabytes), or `g` (gigabytes). If you omit the unit, the system uses bytes. If you omit the size entirely, the system uses `64m`. **--security-opt**=[] Security Options **--stop-signal**=*SIGTERM* Signal to stop a container. Default is SIGTERM. **-t**, **--tty**=*true*|*false* Allocate a pseudo-TTY. The default is *false*. **--tmpfs**=[] Create a tmpfs mount Mount a temporary filesystem (`tmpfs`) mount into a container, for example: $ docker run -d --tmpfs /tmp:rw,size=787448k,mode=1777 my_image This command mounts a `tmpfs` at `/tmp` within the container. The mount copies the underlying content of `my_image` into `/tmp`. For example if there was a directory `/tmp/content` in the base image, docker will copy this directory and all of its content on top of the tmpfs mounted on `/tmp`. The supported mount options are the same as the Linux default `mount` flags. If you do not specify any options, the systems uses the following options: `rw,noexec,nosuid,nodev,size=65536k`. **-u**, **--user**="" Username or UID **--ulimit**=[] Ulimit options **--uts**=*host* Set the UTS mode for the container **host**: use the host's UTS namespace inside the container. Note: the host mode gives the container access to changing the host's hostname and is therefore considered insecure. **-v**, **--volume**=[] Bind mount a volume (e.g., from the host: -v /host:/container, from Docker: -v /container) **--volume-driver**="" Container's volume driver. This driver creates volumes specified either from a Dockerfile's `VOLUME` instruction or from the `docker run -v` flag. See **docker-volume-create(1)** for full details. **--volumes-from**=[] Mount volumes from the specified container(s) **-w**, **--workdir**="" Working directory inside the container # EXAMPLES ## Specify isolation technology for container (--isolation) This option is useful in situations where you are running Docker containers on Windows. The `--isolation=` option sets a container's isolation technology. On Linux, the only supported is the `default` option which uses Linux namespaces. On Microsoft Windows, you can specify these values: * `default`: Use the value specified by the Docker daemon's `--exec-opt` . If the `daemon` does not specify an isolation technology, Microsoft Windows uses `process` as its default value. * `process`: Namespace isolation only. * `hyperv`: Hyper-V hypervisor partition-based isolation. Specifying the `--isolation` flag without a value is the same as setting `--isolation="default"`. # HISTORY August 2014, updated by Sven Dowideit September 2014, updated by Sven Dowideit November 2014, updated by Sven Dowideit