github.com/hustcat/docker@v1.3.3-0.20160314103604-901c67a8eeab/docs/reference/commandline/run.md (about)

     1  <!--[metadata]>
     2  +++
     3  title = "run"
     4  description = "The run command description and usage"
     5  keywords = ["run, command, container"]
     6  [menu.main]
     7  parent = "smn_cli"
     8  +++
     9  <![end-metadata]-->
    10  
    11  # run
    12  
    13      Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...]
    14  
    15      Run a command in a new container
    16  
    17        -a, --attach=[]               Attach to STDIN, STDOUT or STDERR
    18        --add-host=[]                 Add a custom host-to-IP mapping (host:ip)
    19        --blkio-weight=0              Block IO weight (relative weight)
    20        --blkio-weight-device=[]      Block IO weight (relative device weight, format: `DEVICE_NAME:WEIGHT`)
    21        --cpu-shares=0                CPU shares (relative weight)
    22        --cap-add=[]                  Add Linux capabilities
    23        --cap-drop=[]                 Drop Linux capabilities
    24        --cgroup-parent=""            Optional parent cgroup for the container
    25        --cidfile=""                  Write the container ID to the file
    26        --cpu-period=0                Limit CPU CFS (Completely Fair Scheduler) period
    27        --cpu-quota=0                 Limit CPU CFS (Completely Fair Scheduler) quota
    28        --cpuset-cpus=""              CPUs in which to allow execution (0-3, 0,1)
    29        --cpuset-mems=""              Memory nodes (MEMs) in which to allow execution (0-3, 0,1)
    30        -d, --detach                  Run container in background and print container ID
    31        --detach-keys                 Specify the escape key sequence used to detach a container
    32        --device=[]                   Add a host device to the container
    33        --device-read-bps=[]          Limit read rate (bytes per second) from a device (e.g., --device-read-bps=/dev/sda:1mb)
    34        --device-read-iops=[]         Limit read rate (IO per second) from a device (e.g., --device-read-iops=/dev/sda:1000)
    35        --device-write-bps=[]         Limit write rate (bytes per second) to a device (e.g., --device-write-bps=/dev/sda:1mb)
    36        --device-write-iops=[]        Limit write rate (IO per second) to a device (e.g., --device-write-bps=/dev/sda:1000)
    37        --disable-content-trust=true  Skip image verification
    38        --dns=[]                      Set custom DNS servers
    39        --dns-opt=[]                  Set custom DNS options
    40        --dns-search=[]               Set custom DNS search domains
    41        -e, --env=[]                  Set environment variables
    42        --entrypoint=""               Overwrite the default ENTRYPOINT of the image
    43        --env-file=[]                 Read in a file of environment variables
    44        --expose=[]                   Expose a port or a range of ports
    45        --group-add=[]                Add additional groups to run as
    46        -h, --hostname=""             Container host name
    47        --help                        Print usage
    48        -i, --interactive             Keep STDIN open even if not attached
    49        --ip=""                       Container IPv4 address (e.g. 172.30.100.104)
    50        --ip6=""                      Container IPv6 address (e.g. 2001:db8::33)
    51        --ipc=""                      IPC namespace to use
    52        --isolation=""                Container isolation technology
    53        --kernel-memory=""            Kernel memory limit
    54        -l, --label=[]                Set metadata on the container (e.g., --label=com.example.key=value)
    55        --label-file=[]               Read in a file of labels (EOL delimited)
    56        --link=[]                     Add link to another container
    57        --log-driver=""               Logging driver for container
    58        --log-opt=[]                  Log driver specific options
    59        -m, --memory=""               Memory limit
    60        --mac-address=""              Container MAC address (e.g. 92:d0:c6:0a:29:33)
    61        --memory-reservation=""       Memory soft limit
    62        --memory-swap=""              A positive integer equal to memory plus swap. Specify -1 to enable unlimited swap.
    63        --memory-swappiness=""        Tune a container's memory swappiness behavior. Accepts an integer between 0 and 100.
    64        --name=""                     Assign a name to the container
    65        --net="bridge"                Connect a container to a network
    66                                      'bridge': create a network stack on the default Docker bridge
    67                                      'none': no networking
    68                                      'container:<name|id>': reuse another container's network stack
    69                                      'host': use the Docker host network stack
    70                                      '<network-name>|<network-id>': connect to a user-defined network
    71        --net-alias=[]                Add network-scoped alias for the container
    72        --oom-kill-disable            Whether to disable OOM Killer for the container or not
    73        --oom-score-adj=0             Tune the host's OOM preferences for containers (accepts -1000 to 1000)
    74        -P, --publish-all             Publish all exposed ports to random ports
    75        -p, --publish=[]              Publish a container's port(s) to the host
    76        --pid=""                      PID namespace to use
    77        --pids-limit=-1                Tune container pids limit (set -1 for unlimited), kernel >= 4.3
    78        --privileged                  Give extended privileges to this container
    79        --read-only                   Mount the container's root filesystem as read only
    80        --restart="no"                Restart policy (no, on-failure[:max-retry], always, unless-stopped)
    81        --rm                          Automatically remove the container when it exits
    82        --shm-size=[]                 Size of `/dev/shm`. The format is `<number><unit>`. `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`.
    83        --security-opt=[]             Security Options
    84        --sig-proxy=true              Proxy received signals to the process
    85        --stop-signal="SIGTERM"       Signal to stop a container
    86        -t, --tty                     Allocate a pseudo-TTY
    87        -u, --user=""                 Username or UID (format: <name|uid>[:<group|gid>])
    88        --ulimit=[]                   Ulimit options
    89        --uts=""                      UTS namespace to use
    90        -v, --volume=[host-src:]container-dest[:<options>]
    91                                      Bind mount a volume. The comma-delimited
    92                                      `options` are [rw|ro], [z|Z], or
    93                                      [[r]shared|[r]slave|[r]private]. The
    94                                      'host-src' is an absolute path or a name
    95                                      value.
    96        --volume-driver=""            Container's volume driver
    97        --volumes-from=[]             Mount volumes from the specified container(s)
    98        -w, --workdir=""              Working directory inside the container
    99  
   100  The `docker run` command first `creates` a writeable container layer over the
   101  specified image, and then `starts` it using the specified command. That is,
   102  `docker run` is equivalent to the API `/containers/create` then
   103  `/containers/(id)/start`. A stopped container can be restarted with all its
   104  previous changes intact using `docker start`. See `docker ps -a` to view a list
   105  of all containers.
   106  
   107  The `docker run` command can be used in combination with `docker commit` to
   108  [*change the command that a container runs*](commit.md). There is additional detailed information about `docker run` in the [Docker run reference](../run.md).
   109  
   110  For information on connecting a container to a network, see the ["*Docker network overview*"](../../userguide/networking/index.md).
   111  
   112  ## Examples
   113  
   114  ### Assign name and allocate pseudo-TTY (--name, -it)
   115  
   116      $ docker run --name test -it debian
   117      root@d6c0fe130dba:/# exit 13
   118      $ echo $?
   119      13
   120      $ docker ps -a | grep test
   121      d6c0fe130dba        debian:7            "/bin/bash"         26 seconds ago      Exited (13) 17 seconds ago                         test
   122  
   123  This example runs a container named `test` using the `debian:latest`
   124  image. The `-it` instructs Docker to allocate a pseudo-TTY connected to
   125  the container's stdin; creating an interactive `bash` shell in the container.
   126  In the example, the `bash` shell is quit by entering
   127  `exit 13`. This exit code is passed on to the caller of
   128  `docker run`, and is recorded in the `test` container's metadata.
   129  
   130  ### Capture container ID (--cidfile)
   131  
   132      $ docker run --cidfile /tmp/docker_test.cid ubuntu echo "test"
   133  
   134  This will create a container and print `test` to the console. The `cidfile`
   135  flag makes Docker attempt to create a new file and write the container ID to it.
   136  If the file exists already, Docker will return an error. Docker will close this
   137  file when `docker run` exits.
   138  
   139  ### Full container capabilities (--privileged)
   140  
   141      $ docker run -t -i --rm ubuntu bash
   142      root@bc338942ef20:/# mount -t tmpfs none /mnt
   143      mount: permission denied
   144  
   145  This will *not* work, because by default, most potentially dangerous kernel
   146  capabilities are dropped; including `cap_sys_admin` (which is required to mount
   147  filesystems). However, the `--privileged` flag will allow it to run:
   148  
   149      $ docker run -t -i --privileged ubuntu bash
   150      root@50e3f57e16e6:/# mount -t tmpfs none /mnt
   151      root@50e3f57e16e6:/# df -h
   152      Filesystem      Size  Used Avail Use% Mounted on
   153      none            1.9G     0  1.9G   0% /mnt
   154  
   155  The `--privileged` flag gives *all* capabilities to the container, and it also
   156  lifts all the limitations enforced by the `device` cgroup controller. In other
   157  words, the container can then do almost everything that the host can do. This
   158  flag exists to allow special use-cases, like running Docker within Docker.
   159  
   160  ### Set working directory (-w)
   161  
   162      $ docker  run -w /path/to/dir/ -i -t  ubuntu pwd
   163  
   164  The `-w` lets the command being executed inside directory given, here
   165  `/path/to/dir/`. If the path does not exists it is created inside the container.
   166  
   167  ### Mount tmpfs (--tmpfs)
   168  
   169      $ docker run -d --tmpfs /run:rw,noexec,nosuid,size=65536k my_image
   170  
   171  The `--tmpfs` flag mounts an empty tmpfs into the container with the `rw`,
   172  `noexec`, `nosuid`, `size=65536k` options.
   173  
   174  ### Mount volume (-v, --read-only)
   175  
   176      $ docker  run  -v `pwd`:`pwd` -w `pwd` -i -t  ubuntu pwd
   177  
   178  The `-v` flag mounts the current working directory into the container. The `-w`
   179  lets the command being executed inside the current working directory, by
   180  changing into the directory to the value returned by `pwd`. So this
   181  combination executes the command using the container, but inside the
   182  current working directory.
   183  
   184      $ docker run -v /doesnt/exist:/foo -w /foo -i -t ubuntu bash
   185  
   186  When the host directory of a bind-mounted volume doesn't exist, Docker
   187  will automatically create this directory on the host for you. In the
   188  example above, Docker will create the `/doesnt/exist`
   189  folder before starting your container.
   190  
   191      $ docker run --read-only -v /icanwrite busybox touch /icanwrite here
   192  
   193  Volumes can be used in combination with `--read-only` to control where
   194  a container writes files. The `--read-only` flag mounts the container's root
   195  filesystem as read only prohibiting writes to locations other than the
   196  specified volumes for the container.
   197  
   198      $ docker run -t -i -v /var/run/docker.sock:/var/run/docker.sock -v /path/to/static-docker-binary:/usr/bin/docker busybox sh
   199  
   200  By bind-mounting the docker unix socket and statically linked docker
   201  binary (refer to [get the linux binary](
   202  ../../installation/binaries.md#get-the-linux-binary)),
   203  you give the container the full access to create and manipulate the host's
   204  Docker daemon.
   205  
   206  ### Publish or expose port (-p, --expose)
   207  
   208      $ docker run -p 127.0.0.1:80:8080 ubuntu bash
   209  
   210  This binds port `8080` of the container to port `80` on `127.0.0.1` of the host
   211  machine. The [Docker User
   212  Guide](../../userguide/networking/default_network/dockerlinks.md)
   213  explains in detail how to manipulate ports in Docker.
   214  
   215      $ docker run --expose 80 ubuntu bash
   216  
   217  This exposes port `80` of the container without publishing the port to the host
   218  system's interfaces.
   219  
   220  ### Set environment variables (-e, --env, --env-file)
   221  
   222      $ docker run -e MYVAR1 --env MYVAR2=foo --env-file ./env.list ubuntu bash
   223  
   224  This sets simple (non-array) environmental variables in the container. For
   225  illustration all three
   226  flags are shown here. Where `-e`, `--env` take an environment variable and
   227  value, or if no `=` is provided, then that variable's current value is passed
   228  through (i.e. `$MYVAR1` from the host is set to `$MYVAR1` in the container).
   229  When no `=` is provided and that variable is not defined in the client's
   230  environment then that variable will be removed from the container's list of
   231  environment variables.
   232  All three flags, `-e`, `--env` and `--env-file` can be repeated.
   233  
   234  Regardless of the order of these three flags, the `--env-file` are processed
   235  first, and then `-e`, `--env` flags. This way, the `-e` or `--env` will
   236  override variables as needed.
   237  
   238      $ cat ./env.list
   239      TEST_FOO=BAR
   240      $ docker run --env TEST_FOO="This is a test" --env-file ./env.list busybox env | grep TEST_FOO
   241      TEST_FOO=This is a test
   242  
   243  The `--env-file` flag takes a filename as an argument and expects each line
   244  to be in the `VAR=VAL` format, mimicking the argument passed to `--env`. Comment
   245  lines need only be prefixed with `#`
   246  
   247  An example of a file passed with `--env-file`
   248  
   249      $ cat ./env.list
   250      TEST_FOO=BAR
   251  
   252      # this is a comment
   253      TEST_APP_DEST_HOST=10.10.0.127
   254      TEST_APP_DEST_PORT=8888
   255      _TEST_BAR=FOO
   256      TEST_APP_42=magic
   257      helloWorld=true
   258      123qwe=bar
   259      org.spring.config=something
   260  
   261      # pass through this variable from the caller
   262      TEST_PASSTHROUGH
   263      $ TEST_PASSTHROUGH=howdy docker run --env-file ./env.list busybox env
   264      PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
   265      HOSTNAME=5198e0745561
   266      TEST_FOO=BAR
   267      TEST_APP_DEST_HOST=10.10.0.127
   268      TEST_APP_DEST_PORT=8888
   269      _TEST_BAR=FOO
   270      TEST_APP_42=magic
   271      helloWorld=true
   272      TEST_PASSTHROUGH=howdy
   273      HOME=/root
   274      123qwe=bar
   275      org.spring.config=something
   276  
   277      $ docker run --env-file ./env.list busybox env
   278      PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
   279      HOSTNAME=5198e0745561
   280      TEST_FOO=BAR
   281      TEST_APP_DEST_HOST=10.10.0.127
   282      TEST_APP_DEST_PORT=8888
   283      _TEST_BAR=FOO
   284      TEST_APP_42=magic
   285      helloWorld=true
   286      TEST_PASSTHROUGH=
   287      HOME=/root
   288      123qwe=bar
   289      org.spring.config=something
   290  
   291  ### Set metadata on container (-l, --label, --label-file)
   292  
   293  A label is a `key=value` pair that applies metadata to a container. To label a container with two labels:
   294  
   295      $ docker run -l my-label --label com.example.foo=bar ubuntu bash
   296  
   297  The `my-label` key doesn't specify a value so the label defaults to an empty
   298  string(`""`). To add multiple labels, repeat the label flag (`-l` or `--label`).
   299  
   300  The `key=value` must be unique to avoid overwriting the label value. If you
   301  specify labels with identical keys but different values, each subsequent value
   302  overwrites the previous. Docker uses the last `key=value` you supply.
   303  
   304  Use the `--label-file` flag to load multiple labels from a file. Delimit each
   305  label in the file with an EOL mark. The example below loads labels from a
   306  labels file in the current directory:
   307  
   308      $ docker run --label-file ./labels ubuntu bash
   309  
   310  The label-file format is similar to the format for loading environment
   311  variables. (Unlike environment variables, labels are not visible to processes
   312  running inside a container.) The following example illustrates a label-file
   313  format:
   314  
   315      com.example.label1="a label"
   316  
   317      # this is a comment
   318      com.example.label2=another\ label
   319      com.example.label3
   320  
   321  You can load multiple label-files by supplying multiple  `--label-file` flags.
   322  
   323  For additional information on working with labels, see [*Labels - custom
   324  metadata in Docker*](../../userguide/labels-custom-metadata.md) in the Docker User
   325  Guide.
   326  
   327  ### Connect a container to a network (--net)
   328  
   329  When you start a container use the `--net` flag to connect it to a network.
   330  This adds the `busybox` container to the `my-net` network.
   331  
   332  ```bash
   333  $ docker run -itd --net=my-net busybox
   334  ```
   335  
   336  You can also choose the IP addresses for the container with `--ip` and `--ip6`
   337  flags when you start the container on a user-defined network.
   338  
   339  ```bash
   340  $ docker run -itd --net=my-net --ip=10.10.9.75 busybox
   341  ```
   342  
   343  If you want to add a running container to a network use the `docker network connect` subcommand.
   344  
   345  You can connect multiple containers to the same network. Once connected, the
   346  containers can communicate easily need only another container's IP address
   347  or name. For `overlay` networks or custom plugins that support multi-host
   348  connectivity, containers connected to the same multi-host network but launched
   349  from different Engines can also communicate in this way.
   350  
   351  **Note**: Service discovery is unavailable on the default bridge network.
   352  Containers can communicate via their IP addresses by default. To communicate
   353  by name, they must be linked.
   354  
   355  You can disconnect a container from a network using the `docker network
   356  disconnect` command.
   357  
   358  ### Mount volumes from container (--volumes-from)
   359  
   360      $ docker run --volumes-from 777f7dc92da7 --volumes-from ba8c0c54f0f2:ro -i -t ubuntu pwd
   361  
   362  The `--volumes-from` flag mounts all the defined volumes from the referenced
   363  containers. Containers can be specified by repetitions of the `--volumes-from`
   364  argument. The container ID may be optionally suffixed with `:ro` or `:rw` to
   365  mount the volumes in read-only or read-write mode, respectively. By default,
   366  the volumes are mounted in the same mode (read write or read only) as
   367  the reference container.
   368  
   369  Labeling systems like SELinux require that proper labels are placed on volume
   370  content mounted into a container. Without a label, the security system might
   371  prevent the processes running inside the container from using the content. By
   372  default, Docker does not change the labels set by the OS.
   373  
   374  To change the label in the container context, you can add either of two suffixes
   375  `:z` or `:Z` to the volume mount. These suffixes tell Docker to relabel file
   376  objects on the shared volumes. The `z` option tells Docker that two containers
   377  share the volume content. As a result, Docker labels the content with a shared
   378  content label. Shared volume labels allow all containers to read/write content.
   379  The `Z` option tells Docker to label the content with a private unshared label.
   380  Only the current container can use a private volume.
   381  
   382  ### Attach to STDIN/STDOUT/STDERR (-a)
   383  
   384  The `-a` flag tells `docker run` to bind to the container's `STDIN`, `STDOUT`
   385  or `STDERR`. This makes it possible to manipulate the output and input as
   386  needed.
   387  
   388      $ echo "test" | docker run -i -a stdin ubuntu cat -
   389  
   390  This pipes data into a container and prints the container's ID by attaching
   391  only to the container's `STDIN`.
   392  
   393      $ docker run -a stderr ubuntu echo test
   394  
   395  This isn't going to print anything unless there's an error because we've
   396  only attached to the `STDERR` of the container. The container's logs
   397  still store what's been written to `STDERR` and `STDOUT`.
   398  
   399      $ cat somefile | docker run -i -a stdin mybuilder dobuild
   400  
   401  This is how piping a file into a container could be done for a build.
   402  The container's ID will be printed after the build is done and the build
   403  logs could be retrieved using `docker logs`. This is
   404  useful if you need to pipe a file or something else into a container and
   405  retrieve the container's ID once the container has finished running.
   406  
   407  ### Add host device to container (--device)
   408  
   409      $ docker run --device=/dev/sdc:/dev/xvdc --device=/dev/sdd --device=/dev/zero:/dev/nulo -i -t ubuntu ls -l /dev/{xvdc,sdd,nulo}
   410      brw-rw---- 1 root disk 8, 2 Feb  9 16:05 /dev/xvdc
   411      brw-rw---- 1 root disk 8, 3 Feb  9 16:05 /dev/sdd
   412      crw-rw-rw- 1 root root 1, 5 Feb  9 16:05 /dev/nulo
   413  
   414  It is often necessary to directly expose devices to a container. The `--device`
   415  option enables that. For example, a specific block storage device or loop
   416  device or audio device can be added to an otherwise unprivileged container
   417  (without the `--privileged` flag) and have the application directly access it.
   418  
   419  By default, the container will be able to `read`, `write` and `mknod` these devices.
   420  This can be overridden using a third `:rwm` set of options to each `--device`
   421  flag:
   422  
   423  
   424      $ docker run --device=/dev/sda:/dev/xvdc --rm -it ubuntu fdisk  /dev/xvdc
   425  
   426      Command (m for help): q
   427      $ docker run --device=/dev/sda:/dev/xvdc:r --rm -it ubuntu fdisk  /dev/xvdc
   428      You will not be able to write the partition table.
   429  
   430      Command (m for help): q
   431  
   432      $ docker run --device=/dev/sda:/dev/xvdc:rw --rm -it ubuntu fdisk  /dev/xvdc
   433  
   434      Command (m for help): q
   435  
   436      $ docker run --device=/dev/sda:/dev/xvdc:m --rm -it ubuntu fdisk  /dev/xvdc
   437      fdisk: unable to open /dev/xvdc: Operation not permitted
   438  
   439  > **Note:**
   440  > `--device` cannot be safely used with ephemeral devices. Block devices
   441  > that may be removed should not be added to untrusted containers with
   442  > `--device`.
   443  
   444  ### Restart policies (--restart)
   445  
   446  Use Docker's `--restart` to specify a container's *restart policy*. A restart
   447  policy controls whether the Docker daemon restarts a container after exit.
   448  Docker supports the following restart policies:
   449  
   450  <table>
   451    <thead>
   452      <tr>
   453        <th>Policy</th>
   454        <th>Result</th>
   455      </tr>
   456    </thead>
   457    <tbody>
   458      <tr>
   459        <td><strong>no</strong></td>
   460        <td>
   461          Do not automatically restart the container when it exits. This is the
   462          default.
   463        </td>
   464      </tr>
   465      <tr>
   466        <td>
   467          <span style="white-space: nowrap">
   468            <strong>on-failure</strong>[:max-retries]
   469          </span>
   470        </td>
   471        <td>
   472          Restart only if the container exits with a non-zero exit status.
   473          Optionally, limit the number of restart retries the Docker
   474          daemon attempts.
   475        </td>
   476      </tr>
   477      <tr>
   478        <td><strong>always</strong></td>
   479        <td>
   480          Always restart the container regardless of the exit status.
   481          When you specify always, the Docker daemon will try to restart
   482          the container indefinitely. The container will also always start
   483          on daemon startup, regardless of the current state of the container.
   484        </td>
   485      </tr>
   486      <tr>
   487        <td><strong>unless-stopped</strong></td>
   488        <td>
   489          Always restart the container regardless of the exit status, but
   490          do not start it on daemon startup if the container has been put
   491          to a stopped state before.
   492        </td>
   493      </tr>
   494    </tbody>
   495  </table>
   496  
   497      $ docker run --restart=always redis
   498  
   499  This will run the `redis` container with a restart policy of **always**
   500  so that if the container exits, Docker will restart it.
   501  
   502  More detailed information on restart policies can be found in the
   503  [Restart Policies (--restart)](../run.md#restart-policies-restart)
   504  section of the Docker run reference page.
   505  
   506  ### Add entries to container hosts file (--add-host)
   507  
   508  You can add other hosts into a container's `/etc/hosts` file by using one or
   509  more `--add-host` flags. This example adds a static address for a host named
   510  `docker`:
   511  
   512      $ docker run --add-host=docker:10.180.0.1 --rm -it debian
   513      $$ ping docker
   514      PING docker (10.180.0.1): 48 data bytes
   515      56 bytes from 10.180.0.1: icmp_seq=0 ttl=254 time=7.600 ms
   516      56 bytes from 10.180.0.1: icmp_seq=1 ttl=254 time=30.705 ms
   517      ^C--- docker ping statistics ---
   518      2 packets transmitted, 2 packets received, 0% packet loss
   519      round-trip min/avg/max/stddev = 7.600/19.152/30.705/11.553 ms
   520  
   521  Sometimes you need to connect to the Docker host from within your
   522  container. To enable this, pass the Docker host's IP address to
   523  the container using the `--add-host` flag. To find the host's address,
   524  use the `ip addr show` command.
   525  
   526  The flags you pass to `ip addr show` depend on whether you are
   527  using IPv4 or IPv6 networking in your containers. Use the following
   528  flags for IPv4 address retrieval for a network device named `eth0`:
   529  
   530      $ HOSTIP=`ip -4 addr show scope global dev eth0 | grep inet | awk '{print \$2}' | cut -d / -f 1`
   531      $ docker run  --add-host=docker:${HOSTIP} --rm -it debian
   532  
   533  For IPv6 use the `-6` flag instead of the `-4` flag. For other network
   534  devices, replace `eth0` with the correct device name (for example `docker0`
   535  for the bridge device).
   536  
   537  ### Set ulimits in container (--ulimit)
   538  
   539  Since setting `ulimit` settings in a container requires extra privileges not
   540  available in the default container, you can set these using the `--ulimit` flag.
   541  `--ulimit` is specified with a soft and hard limit as such:
   542  `<type>=<soft limit>[:<hard limit>]`, for example:
   543  
   544      $ docker run --ulimit nofile=1024:1024 --rm debian sh -c "ulimit -n"
   545      1024
   546  
   547  > **Note:**
   548  > If you do not provide a `hard limit`, the `soft limit` will be used
   549  > for both values. If no `ulimits` are set, they will be inherited from
   550  > the default `ulimits` set on the daemon.  `as` option is disabled now.
   551  > In other words, the following script is not supported:
   552  > `$ docker run -it --ulimit as=1024 fedora /bin/bash`
   553  
   554  The values are sent to the appropriate `syscall` as they are set.
   555  Docker doesn't perform any byte conversion. Take this into account when setting the values.
   556  
   557  #### For `nproc` usage
   558  
   559  Be careful setting `nproc` with the `ulimit` flag as `nproc` is designed by Linux to set the
   560  maximum number of processes available to a user, not to a container.  For example, start four
   561  containers with `daemon` user:
   562  
   563      docker run -d -u daemon --ulimit nproc=3 busybox top
   564      docker run -d -u daemon --ulimit nproc=3 busybox top
   565      docker run -d -u daemon --ulimit nproc=3 busybox top
   566      docker run -d -u daemon --ulimit nproc=3 busybox top
   567  
   568  The 4th container fails and reports "[8] System error: resource temporarily unavailable" error.
   569  This fails because the caller set `nproc=3` resulting in the first three containers using up
   570  the three processes quota set for the `daemon` user.
   571  
   572  ### Stop container with signal (--stop-signal)
   573  
   574  The `--stop-signal` flag sets the system call signal that will be sent to the container to exit.
   575  This signal can be a valid unsigned number that matches a position in the kernel's syscall table, for instance 9,
   576  or a signal name in the format SIGNAME, for instance SIGKILL.
   577  
   578  ### Specify isolation technology for container (--isolation)
   579  
   580  This option is useful in situations where you are running Docker containers on
   581  Microsoft Windows. The `--isolation <value>` option sets a container's isolation
   582  technology. On Linux, the only supported is the `default` option which uses
   583  Linux namespaces. These two commands are equivalent on Linux:
   584  
   585  ```
   586  $ docker run -d busybox top
   587  $ docker run -d --isolation default busybox top
   588  ```
   589  
   590  On Microsoft Windows, can take any of these values:
   591  
   592  
   593  | Value     | Description                                                                                                                                                   |
   594  |-----------|---------------------------------------------------------------------------------------------------------------------------------------------------------------|
   595  | `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.  |
   596  | `process` | Namespace isolation only.                                                                                                                                     |
   597  | `hyperv`   | Hyper-V hypervisor partition-based isolation.                                                                                                                  |
   598  
   599  In practice, when running on Microsoft Windows without a `daemon` option set,  these two commands are equivalent:
   600  
   601  ```
   602  $ docker run -d --isolation default busybox top
   603  $ docker run -d --isolation process busybox top
   604  ```
   605  
   606  If you have set the `--exec-opt isolation=hyperv` option on the Docker `daemon`, any of these commands also result in `hyperv` isolation:
   607  
   608  ```
   609  $ docker run -d --isolation default busybox top
   610  $ docker run -d --isolation hyperv busybox top
   611  ```