github.com/docker/docker-ce@v17.12.1-ce-rc2+incompatible/components/cli/man/docker-run.1.md (about)

     1  % DOCKER(1) Docker User Manuals
     2  % Docker Community
     3  % JUNE 2014
     4  # NAME
     5  docker-run - Run a command in a new container
     6  
     7  # SYNOPSIS
     8  **docker run**
     9  [**-a**|**--attach**[=*[]*]]
    10  [**--add-host**[=*[]*]]
    11  [**--blkio-weight**[=*[BLKIO-WEIGHT]*]]
    12  [**--blkio-weight-device**[=*[]*]]
    13  [**--cpu-shares**[=*0*]]
    14  [**--cap-add**[=*[]*]]
    15  [**--cap-drop**[=*[]*]]
    16  [**--cgroup-parent**[=*CGROUP-PATH*]]
    17  [**--cidfile**[=*CIDFILE*]]
    18  [**--cpu-count**[=*0*]]
    19  [**--cpu-percent**[=*0*]]
    20  [**--cpu-period**[=*0*]]
    21  [**--cpu-quota**[=*0*]]
    22  [**--cpu-rt-period**[=*0*]]
    23  [**--cpu-rt-runtime**[=*0*]]
    24  [**--cpus**[=*0.0*]]
    25  [**--cpuset-cpus**[=*CPUSET-CPUS*]]
    26  [**--cpuset-mems**[=*CPUSET-MEMS*]]
    27  [**-d**|**--detach**]
    28  [**--detach-keys**[=*[]*]]
    29  [**--device**[=*[]*]]
    30  [**--device-cgroup-rule**[=*[]*]]
    31  [**--device-read-bps**[=*[]*]]
    32  [**--device-read-iops**[=*[]*]]
    33  [**--device-write-bps**[=*[]*]]
    34  [**--device-write-iops**[=*[]*]]
    35  [**--dns**[=*[]*]]
    36  [**--dns-option**[=*[]*]]
    37  [**--dns-search**[=*[]*]]
    38  [**-e**|**--env**[=*[]*]]
    39  [**--entrypoint**[=*ENTRYPOINT*]]
    40  [**--env-file**[=*[]*]]
    41  [**--expose**[=*[]*]]
    42  [**--group-add**[=*[]*]]
    43  [**-h**|**--hostname**[=*HOSTNAME*]]
    44  [**--help**]
    45  [**--init**]
    46  [**-i**|**--interactive**]
    47  [**--ip**[=*IPv4-ADDRESS*]]
    48  [**--ip6**[=*IPv6-ADDRESS*]]
    49  [**--ipc**[=*IPC*]]
    50  [**--isolation**[=*default*]]
    51  [**--kernel-memory**[=*KERNEL-MEMORY*]]
    52  [**-l**|**--label**[=*[]*]]
    53  [**--label-file**[=*[]*]]
    54  [**--link**[=*[]*]]
    55  [**--link-local-ip**[=*[]*]]
    56  [**--log-driver**[=*[]*]]
    57  [**--log-opt**[=*[]*]]
    58  [**-m**|**--memory**[=*MEMORY*]]
    59  [**--mac-address**[=*MAC-ADDRESS*]]
    60  [**--memory-reservation**[=*MEMORY-RESERVATION*]]
    61  [**--memory-swap**[=*LIMIT*]]
    62  [**--memory-swappiness**[=*MEMORY-SWAPPINESS*]]
    63  [**--mount**[=*[MOUNT]*]]
    64  [**--name**[=*NAME*]]
    65  [**--network-alias**[=*[]*]]
    66  [**--network**[=*"bridge"*]]
    67  [**--oom-kill-disable**]
    68  [**--oom-score-adj**[=*0*]]
    69  [**-P**|**--publish-all**]
    70  [**-p**|**--publish**[=*[]*]]
    71  [**--pid**[=*[PID]*]]
    72  [**--userns**[=*[]*]]
    73  [**--pids-limit**[=*PIDS_LIMIT*]]
    74  [**--privileged**]
    75  [**--read-only**]
    76  [**--restart**[=*RESTART*]]
    77  [**--rm**]
    78  [**--security-opt**[=*[]*]]
    79  [**--storage-opt**[=*[]*]]
    80  [**--stop-signal**[=*SIGNAL*]]
    81  [**--stop-timeout**[=*TIMEOUT*]]
    82  [**--shm-size**[=*[]*]]
    83  [**--sig-proxy**[=*true*]]
    84  [**--sysctl**[=*[]*]]
    85  [**-t**|**--tty**]
    86  [**--tmpfs**[=*[CONTAINER-DIR[:<OPTIONS>]*]]
    87  [**-u**|**--user**[=*USER*]]
    88  [**--ulimit**[=*[]*]]
    89  [**--uts**[=*[]*]]
    90  [**-v**|**--volume**[=*[[HOST-DIR:]CONTAINER-DIR[:OPTIONS]]*]]
    91  [**--volume-driver**[=*DRIVER*]]
    92  [**--volumes-from**[=*[]*]]
    93  [**-w**|**--workdir**[=*WORKDIR*]]
    94  IMAGE [COMMAND] [ARG...]
    95  
    96  # DESCRIPTION
    97  
    98  Run a process in a new container. **docker run** starts a process with its own
    99  file system, its own networking, and its own isolated process tree. The IMAGE
   100  which starts the process may define defaults related to the process that will be
   101  run in the container, the networking to expose, and more, but **docker run**
   102  gives final control to the operator or administrator who starts the container
   103  from the image. For that reason **docker run** has more options than any other
   104  Docker command.
   105  
   106  If the IMAGE is not already loaded then **docker run** will pull the IMAGE, and
   107  all image dependencies, from the repository in the same way running **docker
   108  pull** IMAGE, before it starts the container from that image.
   109  
   110  # OPTIONS
   111  **-a**, **--attach**=[]
   112     Attach to STDIN, STDOUT or STDERR.
   113  
   114     In foreground mode (the default when **-d**
   115  is not specified), **docker run** can start the process in the container
   116  and attach the console to the process's standard input, output, and standard
   117  error. It can even pretend to be a TTY (this is what most commandline
   118  executables expect) and pass along signals. The **-a** option can be set for
   119  each of stdin, stdout, and stderr.
   120  
   121  **--add-host**=[]
   122     Add a custom host-to-IP mapping (host:ip)
   123  
   124     Add a line to /etc/hosts. The format is hostname:ip.  The **--add-host**
   125  option can be set multiple times.
   126  
   127  **--blkio-weight**=*0*
   128     Block IO weight (relative weight) accepts a weight value between 10 and 1000.
   129  
   130  **--blkio-weight-device**=[]
   131     Block IO weight (relative device weight, format: `DEVICE_NAME:WEIGHT`).
   132  
   133  **--cpu-shares**=*0*
   134     CPU shares (relative weight)
   135  
   136     By default, all containers get the same proportion of CPU cycles. This proportion
   137  can be modified by changing the container's CPU share weighting relative
   138  to the weighting of all other running containers.
   139  
   140  To modify the proportion from the default of 1024, use the **--cpu-shares**
   141  flag to set the weighting to 2 or higher.
   142  
   143  The proportion will only apply when CPU-intensive processes are running.
   144  When tasks in one container are idle, other containers can use the
   145  left-over CPU time. The actual amount of CPU time will vary depending on
   146  the number of containers running on the system.
   147  
   148  For example, consider three containers, one has a cpu-share of 1024 and
   149  two others have a cpu-share setting of 512. When processes in all three
   150  containers attempt to use 100% of CPU, the first container would receive
   151  50% of the total CPU time. If you add a fourth container with a cpu-share
   152  of 1024, the first container only gets 33% of the CPU. The remaining containers
   153  receive 16.5%, 16.5% and 33% of the CPU.
   154  
   155  On a multi-core system, the shares of CPU time are distributed over all CPU
   156  cores. Even if a container is limited to less than 100% of CPU time, it can
   157  use 100% of each individual CPU core.
   158  
   159  For example, consider a system with more than three cores. If you start one
   160  container **{C0}** with **-c=512** running one process, and another container
   161  **{C1}** with **-c=1024** running two processes, this can result in the following
   162  division of CPU shares:
   163  
   164      PID    container	CPU	CPU share
   165      100    {C0}		0	100% of CPU0
   166      101    {C1}		1	100% of CPU1
   167      102    {C1}		2	100% of CPU2
   168  
   169  **--cap-add**=[]
   170     Add Linux capabilities
   171  
   172  **--cap-drop**=[]
   173     Drop Linux capabilities
   174  
   175  **--cgroup-parent**=""
   176     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.
   177  
   178  **--cidfile**=""
   179     Write the container ID to the file
   180  
   181  **--cpu-count**=*0*
   182      Limit the number of CPUs available for execution by the container.
   183      
   184      On Windows Server containers, this is approximated as a percentage of total CPU usage.
   185  
   186      On Windows Server containers, the processor resource controls are mutually exclusive, the order of precedence is CPUCount first, then CPUShares, and CPUPercent last.
   187  
   188  **--cpu-percent**=*0*
   189      Limit the percentage of CPU available for execution by a container running on a Windows daemon.
   190  
   191      On Windows Server containers, the processor resource controls are mutually exclusive, the order of precedence is CPUCount first, then CPUShares, and CPUPercent last.
   192  
   193  **--cpu-period**=*0*
   194     Limit the CPU CFS (Completely Fair Scheduler) period
   195  
   196     Limit the container's CPU usage. This flag tell the kernel to restrict the container's CPU usage to the period you specify.
   197  
   198  **--cpuset-cpus**=""
   199     CPUs in which to allow execution (0-3, 0,1)
   200  
   201  **--cpuset-mems**=""
   202     Memory nodes (MEMs) in which to allow execution (0-3, 0,1). Only effective on NUMA systems.
   203  
   204     If you have four memory nodes on your system (0-3), use `--cpuset-mems=0,1`
   205  then processes in your Docker container will only use memory from the first
   206  two memory nodes.
   207  
   208  **--cpu-quota**=*0*
   209     Limit the CPU CFS (Completely Fair Scheduler) quota
   210  
   211     Limit the container's CPU usage. By default, containers run with the full
   212  CPU resource. This flag tell the kernel to restrict the container's CPU usage
   213  to the quota you specify.
   214  
   215  **--cpu-rt-period**=0
   216     Limit the CPU real-time period in microseconds
   217  
   218     Limit the container's Real Time CPU usage. This flag tell the kernel to restrict the container's Real Time CPU usage to the period you specify.
   219  
   220  **--cpu-rt-runtime**=0
   221     Limit the CPU real-time runtime in microseconds
   222  
   223     Limit the containers Real Time CPU usage. This flag tells the kernel to limit the amount of time in a given CPU period Real Time tasks may consume. Ex:
   224     Period of 1,000,000us and Runtime of 950,000us means that this container could consume 95% of available CPU and leave the remaining 5% to normal priority tasks.
   225  
   226     The sum of all runtimes across containers cannot exceed the amount allotted to the parent cgroup.
   227  
   228  **--cpus**=0.0
   229     Number of CPUs. The default is *0.0* which means no limit.
   230  
   231  **-d**, **--detach**=*true*|*false*
   232     Detached mode: run the container in the background and print the new container ID. The default is *false*.
   233  
   234     At any time you can run **docker ps** in
   235  the other shell to view a list of the running containers. You can reattach to a
   236  detached container with **docker attach**.
   237  
   238     When attached in the tty mode, you can detach from the container (and leave it
   239  running) using a configurable key sequence. The default sequence is `CTRL-p CTRL-q`.
   240  You configure the key sequence using the **--detach-keys** option or a configuration file.
   241  See **config-json(5)** for documentation on using a configuration file.
   242  
   243  **--detach-keys**=""
   244     Override the key sequence for detaching a container. Format is a single character `[a-Z]` or `ctrl-<value>` where `<value>` is one of: `a-z`, `@`, `^`, `[`, `,` or `_`.
   245  
   246  **--device**=[]
   247     Add a host device to the container (e.g. --device=/dev/sdc:/dev/xvdc:rwm)
   248  
   249  **--device-cgroup-rule**=[]
   250     Add a rule to the cgroup allowed devices list.
   251     
   252     The rule is expected to be in the format specified in the Linux kernel documentation (Documentation/cgroup-v1/devices.txt):
   253       - type: `a` (all), `c` (char) or `b` (block)
   254       - major and minor: either a number or `*` for all
   255       - permission: a composition of `r` (read), `w` (write) and `m` (mknod)
   256  
   257     Example: `c 1:3 mr`: allow for character device with major `1` and minor `3` to be created (`m`) and read (`r`)
   258  
   259  **--device-read-bps**=[]
   260     Limit read rate from a device (e.g. --device-read-bps=/dev/sda:1mb)
   261  
   262  **--device-read-iops**=[]
   263     Limit read rate from a device (e.g. --device-read-iops=/dev/sda:1000)
   264  
   265  **--device-write-bps**=[]
   266     Limit write rate to a device (e.g. --device-write-bps=/dev/sda:1mb)
   267  
   268  **--device-write-iops**=[]
   269     Limit write rate to a device (e.g. --device-write-iops=/dev/sda:1000)
   270  
   271  **--dns-search**=[]
   272     Set custom DNS search domains (Use --dns-search=. if you don't wish to set the search domain)
   273  
   274  **--dns-option**=[]
   275     Set custom DNS options
   276  
   277  **--dns**=[]
   278     Set custom DNS servers
   279  
   280     This option can be used to override the DNS
   281  configuration passed to the container. Typically this is necessary when the
   282  host DNS configuration is invalid for the container (e.g., 127.0.0.1). When this
   283  is the case the **--dns** flags is necessary for every run.
   284  
   285  **-e**, **--env**=[]
   286     Set environment variables
   287  
   288     This option allows you to specify arbitrary
   289  environment variables that are available for the process that will be launched
   290  inside of the container.
   291  
   292  **--entrypoint**=""
   293     Overwrite the default ENTRYPOINT of the image
   294  
   295     This option allows you to overwrite the default entrypoint of the image that
   296  is set in the Dockerfile. The ENTRYPOINT of an image is similar to a COMMAND
   297  because it specifies what executable to run when the container starts, but it is
   298  (purposely) more difficult to override. The ENTRYPOINT gives a container its
   299  default nature or behavior, so that when you set an ENTRYPOINT you can run the
   300  container as if it were that binary, complete with default options, and you can
   301  pass in more options via the COMMAND. But, sometimes an operator may want to run
   302  something else inside the container, so you can override the default ENTRYPOINT
   303  at runtime by using a **--entrypoint** and a string to specify the new
   304  ENTRYPOINT.
   305  
   306  **--env-file**=[]
   307     Read in a line delimited file of environment variables
   308  
   309  **--expose**=[]
   310     Expose a port, or a range of ports (e.g. --expose=3300-3310) informs Docker
   311  that the container listens on the specified network ports at runtime. Docker
   312  uses this information to interconnect containers using links and to set up port
   313  redirection on the host system.
   314  
   315  **--group-add**=[]
   316     Add additional groups to run as
   317  
   318  **-h**, **--hostname**=""
   319     Container host name
   320  
   321     Sets the container host name that is available inside the container.
   322  
   323  **--help**
   324     Print usage statement
   325  
   326  **--init**
   327     Run an init inside the container that forwards signals and reaps processes
   328  
   329  **-i**, **--interactive**=*true*|*false*
   330     Keep STDIN open even if not attached. The default is *false*.
   331  
   332     When set to true, keep stdin open even if not attached. The default is false.
   333  
   334  **--ip**=""
   335     Sets the container's interface IPv4 address (e.g., 172.23.0.9)
   336  
   337     It can only be used in conjunction with **--network** for user-defined networks
   338  
   339  **--ip6**=""
   340     Sets the container's interface IPv6 address (e.g., 2001:db8::1b99)
   341  
   342     It can only be used in conjunction with **--network** for user-defined networks
   343  
   344  **--ipc**=""
   345     Default is to create a private IPC namespace (POSIX SysV IPC) for the container
   346                                 'container:<name|id>': reuses another container shared memory, semaphores and message queues
   347                                 '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.
   348  
   349  **--isolation**="*default*"
   350     Isolation specifies the type of isolation technology used by containers. Note
   351  that the default on Windows server is `process`, and the default on Windows client
   352  is `hyperv`. Linux only supports `default`.
   353  
   354  **-l**, **--label**=[]
   355     Set metadata on the container (e.g., --label com.example.key=value)
   356  
   357  **--kernel-memory**=""
   358     Kernel memory limit (format: `<number>[<unit>]`, where unit = b, k, m or g)
   359  
   360     Constrains the kernel memory available to a container. If a limit of 0
   361  is specified (not using `--kernel-memory`), the container's kernel memory
   362  is not limited. If you specify a limit, it may be rounded up to a multiple
   363  of the operating system's page size and the value can be very large,
   364  millions of trillions.
   365  
   366  **--label-file**=[]
   367     Read in a line delimited file of labels
   368  
   369  **--link**=[]
   370     Add link to another container in the form of <name or id>:alias or just <name or id>
   371  in which case the alias will match the name
   372  
   373     If the operator
   374  uses **--link** when starting the new client container, then the client
   375  container can access the exposed port via a private networking interface. Docker
   376  will set some environment variables in the client container to help indicate
   377  which interface and port to use.
   378  
   379  **--link-local-ip**=[]
   380     Add one or more link-local IPv4/IPv6 addresses to the container's interface
   381  
   382  **--log-driver**="*json-file*|*syslog*|*journald*|*gelf*|*fluentd*|*awslogs*|*splunk*|*etwlogs*|*gcplogs*|*none*"
   383    Logging driver for the container. Default is defined by daemon `--log-driver` flag.
   384    **Warning**: the `docker logs` command works only for the `json-file` and
   385    `journald` logging drivers.
   386  
   387  **--log-opt**=[]
   388    Logging driver specific options.
   389  
   390  **-m**, **--memory**=""
   391     Memory limit (format: <number>[<unit>], where unit = b, k, m or g)
   392  
   393     Allows you to constrain the memory available to a container. If the host
   394  supports swap memory, then the **-m** memory setting can be larger than physical
   395  RAM. If a limit of 0 is specified (not using **-m**), the container's memory is
   396  not limited. The actual limit may be rounded up to a multiple of the operating
   397  system's page size (the value would be very large, that's millions of trillions).
   398  
   399  **--memory-reservation**=""
   400     Memory soft limit (format: <number>[<unit>], where unit = b, k, m or g)
   401  
   402     After setting memory reservation, when the system detects memory contention
   403  or low memory, containers are forced to restrict their consumption to their
   404  reservation. So you should always set the value below **--memory**, otherwise the
   405  hard limit will take precedence. By default, memory reservation will be the same
   406  as memory limit.
   407  
   408  **--memory-swap**="LIMIT"
   409     A limit value equal to memory plus swap. Must be used with the  **-m**
   410  (**--memory**) flag. The swap `LIMIT` should always be larger than **-m**
   411  (**--memory**) value.  By default, the swap `LIMIT` will be set to double
   412  the value of --memory.
   413  
   414     The format of `LIMIT` is `<number>[<unit>]`. Unit can be `b` (bytes),
   415  `k` (kilobytes), `m` (megabytes), or `g` (gigabytes). If you don't specify a
   416  unit, `b` is used. Set LIMIT to `-1` to enable unlimited swap.
   417  
   418  **--mac-address**=""
   419     Container MAC address (e.g., 92:d0:c6:0a:29:33)
   420  
   421     Remember that the MAC address in an Ethernet network must be unique.
   422  The IPv6 link-local address will be based on the device's MAC address
   423  according to RFC4862.
   424  
   425  **--mount**=[*[type=TYPE[,TYPE-SPECIFIC-OPTIONS]]*]
   426     Attach a filesystem mount to the container
   427  
   428     Current supported mount `TYPES` are `bind`, `volume`, and `tmpfs`.
   429  
   430     e.g.
   431  
   432     `type=bind,source=/path/on/host,destination=/path/in/container`
   433  
   434     `type=volume,source=my-volume,destination=/path/in/container,volume-label="color=red",volume-label="shape=round"`
   435  
   436     `type=tmpfs,tmpfs-size=512M,destination=/path/in/container`
   437  
   438     Common Options:
   439  
   440     * `src`, `source`: mount source spec for `bind` and `volume`. Mandatory for `bind`.
   441     * `dst`, `destination`, `target`: mount destination spec.
   442     * `ro`, `read-only`: `true` or `false` (default).
   443  
   444     Options specific to `bind`:
   445  
   446     * `bind-propagation`: `shared`, `slave`, `private`, `rshared`, `rslave`, or `rprivate`(default). See also `mount(2)`.
   447     * `consistency`: `consistent`(default), `cached`, or `delegated`. Currently, only effective for Docker for Mac.
   448  
   449     Options specific to `volume`:
   450  
   451     * `volume-driver`: Name of the volume-driver plugin.
   452     * `volume-label`: Custom metadata.
   453     * `volume-nocopy`: `true`(default) or `false`. If set to `false`, the Engine copies existing files and directories under the mount-path into the volume, allowing the host to access them.
   454     * `volume-opt`: specific to a given volume driver.
   455  
   456     Options specific to `tmpfs`:
   457  
   458     * `tmpfs-size`: Size of the tmpfs mount in bytes. Unlimited by default in Linux.
   459     * `tmpfs-mode`: File mode of the tmpfs in octal. (e.g. `700` or `0700`.) Defaults to `1777` in Linux.
   460  
   461  **--name**=""
   462     Assign a name to the container
   463  
   464     The operator can identify a container in three ways:
   465      UUID long identifier (“f78375b1c487e03c9438c729345e54db9d20cfa2ac1fc3494b6eb60872e74778”)
   466      UUID short identifier (“f78375b1c487”)
   467      Name (“jonah”)
   468  
   469     The UUID identifiers come from the Docker daemon, and if a name is not assigned
   470  to the container with **--name** then the daemon will also generate a random
   471  string name. The name is useful when defining links (see **--link**) (or any
   472  other place you need to identify a container). This works for both background
   473  and foreground Docker containers.
   474  
   475  **--network**="*bridge*"
   476     Set the Network mode for the container
   477                                 'bridge': create a network stack on the default Docker bridge
   478                                 'none': no networking
   479                                 'container:<name|id>': reuse another container's network stack
   480                                 '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.
   481                                 '<network-name>|<network-id>': connect to a user-defined network
   482  
   483  **--network-alias**=[]
   484     Add network-scoped alias for the container
   485  
   486  **--oom-kill-disable**=*true*|*false*
   487     Whether to disable OOM Killer for the container or not.
   488  
   489  **--oom-score-adj**=""
   490     Tune the host's OOM preferences for containers (accepts -1000 to 1000)
   491  
   492  **-P**, **--publish-all**=*true*|*false*
   493     Publish all exposed ports to random ports on the host interfaces. The default is *false*.
   494  
   495     When set to true publish all exposed ports to the host interfaces. The
   496  default is false. If the operator uses -P (or -p) then Docker will make the
   497  exposed port accessible on the host and the ports will be available to any
   498  client that can reach the host. When using -P, Docker will bind any exposed
   499  port to a random port on the host within an *ephemeral port range* defined by
   500  `/proc/sys/net/ipv4/ip_local_port_range`. To find the mapping between the host
   501  ports and the exposed ports, use `docker port`.
   502  
   503  **-p**, **--publish**=[]
   504     Publish a container's port, or range of ports, to the host.
   505  
   506     Format: `ip:hostPort:containerPort | ip::containerPort | hostPort:containerPort | containerPort`
   507  Both hostPort and containerPort can be specified as a range of ports.
   508  When specifying ranges for both, the number of container ports in the range must match the number of host ports in the range.
   509  (e.g., `docker run -p 1234-1236:1222-1224 --name thisWorks -t busybox`
   510  but not `docker run -p 1230-1236:1230-1240 --name RangeContainerPortsBiggerThanRangeHostPorts -t busybox`)
   511  With ip: `docker run -p 127.0.0.1:$HOSTPORT:$CONTAINERPORT --name CONTAINER -t someimage`
   512  Use `docker port` to see the actual mapping: `docker port CONTAINER $CONTAINERPORT`
   513  
   514  **--pid**=""
   515     Set the PID mode for the container
   516     Default is to create a private PID namespace for the container
   517                                 'container:<name|id>': join another container's PID namespace
   518                                 'host': use the host's PID namespace for the container. Note: the host mode gives the container full access to local PID and is therefore considered insecure.
   519  
   520  **--userns**=""
   521     Set the usernamespace mode for the container when `userns-remap` option is enabled.
   522       **host**: use the host usernamespace and enable all privileged options (e.g., `pid=host` or `--privileged`).
   523  
   524  **--pids-limit**=""
   525     Tune the container's pids limit. Set `-1` to have unlimited pids for the container.
   526  
   527  **--uts**=*host*
   528     Set the UTS mode for the container
   529       **host**: use the host's UTS namespace inside the container.
   530       Note: the host mode gives the container access to changing the host's hostname and is therefore considered insecure.
   531  
   532  **--privileged**=*true*|*false*
   533     Give extended privileges to this container. The default is *false*.
   534  
   535     By default, Docker containers are
   536  “unprivileged” (=false) and cannot, for example, run a Docker daemon inside the
   537  Docker container. This is because by default a container is not allowed to
   538  access any devices. A “privileged” container is given access to all devices.
   539  
   540     When the operator executes **docker run --privileged**, Docker will enable access
   541  to all devices on the host as well as set some configuration in AppArmor to
   542  allow the container nearly all the same access to the host as processes running
   543  outside of a container on the host.
   544  
   545  **--read-only**=*true*|*false*
   546     Mount the container's root filesystem as read only.
   547  
   548     By default a container will have its root filesystem writable allowing processes
   549  to write files anywhere.  By specifying the `--read-only` flag the container will have
   550  its root filesystem mounted as read only prohibiting any writes.
   551  
   552  **--restart**="*no*"
   553     Restart policy to apply when a container exits (no, on-failure[:max-retry], always, unless-stopped).
   554  
   555  **--rm**=*true*|*false*
   556     Automatically remove the container when it exits. The default is *false*.
   557     `--rm` flag can work together with `-d`, and auto-removal will be done on daemon side. Note that it's
   558  incompatible with any restart policy other than `none`.
   559  
   560  **--security-opt**=[]
   561     Security Options
   562  
   563      "label=user:USER"   : Set the label user for the container
   564      "label=role:ROLE"   : Set the label role for the container
   565      "label=type:TYPE"   : Set the label type for the container
   566      "label=level:LEVEL" : Set the label level for the container
   567      "label=disable"     : Turn off label confinement for the container
   568      "no-new-privileges" : Disable container processes from gaining additional privileges
   569  
   570      "seccomp=unconfined" : Turn off seccomp confinement for the container
   571      "seccomp=profile.json :  White listed syscalls seccomp Json file to be used as a seccomp filter
   572  
   573      "apparmor=unconfined" : Turn off apparmor confinement for the container
   574      "apparmor=your-profile" : Set the apparmor confinement profile for the container
   575  
   576  **--storage-opt**=[]
   577     Storage driver options per container
   578  
   579     $ docker run -it --storage-opt size=120G fedora /bin/bash
   580  
   581     This (size) will allow to set the container rootfs size to 120G at creation time.
   582     This option is only available for the `devicemapper`, `btrfs`, `overlay2`  and `zfs` graph drivers.
   583     For the `devicemapper`, `btrfs` and `zfs` storage drivers, user cannot pass a size less than the Default BaseFS Size.
   584     For the `overlay2` storage driver, the size option is only available if the backing fs is `xfs` and mounted with the `pquota` mount option.
   585     Under these conditions, user can pass any size less than the backing fs size.
   586  
   587  **--stop-signal**=*SIGTERM*
   588    Signal to stop a container. Default is SIGTERM.
   589  
   590  **--stop-timeout**=*10*
   591    Timeout (in seconds) to stop a container. Default is 10.
   592  
   593  **--shm-size**=""
   594     Size of `/dev/shm`. The format is `<number><unit>`.
   595     `number` must be greater than `0`.  Unit is optional and can be `b` (bytes), `k` (kilobytes), `m`(megabytes), or `g` (gigabytes).
   596     If you omit the unit, the system uses bytes. If you omit the size entirely, the system uses `64m`.
   597  
   598  **--sysctl**=SYSCTL
   599    Configure namespaced kernel parameters at runtime
   600  
   601    IPC Namespace - current sysctls allowed:
   602  
   603    kernel.msgmax, kernel.msgmnb, kernel.msgmni, kernel.sem, kernel.shmall, kernel.shmmax, kernel.shmmni, kernel.shm_rmid_forced
   604    Sysctls beginning with fs.mqueue.*
   605  
   606    If you use the `--ipc=host` option these sysctls will not be allowed.
   607  
   608    Network Namespace - current sysctls allowed:
   609        Sysctls beginning with net.*
   610  
   611    If you use the `--network=host` option these sysctls will not be allowed.
   612  
   613  **--sig-proxy**=*true*|*false*
   614     Proxy received signals to the process (non-TTY mode only). SIGCHLD, SIGSTOP, and SIGKILL are not proxied. The default is *true*.
   615  
   616  **--memory-swappiness**=""
   617     Tune a container's memory swappiness behavior. Accepts an integer between 0 and 100.
   618  
   619  **-t**, **--tty**=*true*|*false*
   620     Allocate a pseudo-TTY. The default is *false*.
   621  
   622     When set to true Docker can allocate a pseudo-tty and attach to the standard
   623  input of any container. This can be used, for example, to run a throwaway
   624  interactive shell. The default is false.
   625  
   626  The **-t** option is incompatible with a redirection of the docker client
   627  standard input.
   628  
   629  **--tmpfs**=[] Create a tmpfs mount
   630  
   631     Mount a temporary filesystem (`tmpfs`) mount into a container, for example:
   632  
   633     $ docker run -d --tmpfs /tmp:rw,size=787448k,mode=1777 my_image
   634  
   635     This command mounts a `tmpfs` at `/tmp` within the container.  The supported mount
   636  options are the same as the Linux default `mount` flags. If you do not specify
   637  any options, the systems uses the following options:
   638  `rw,noexec,nosuid,nodev,size=65536k`.
   639  
   640     See also `--mount`, which is the successor of `--tmpfs` and `--volume`.
   641     Even though there is no plan to deprecate `--tmpfs`, usage of `--mount` is recommended.
   642  
   643  **-u**, **--user**=""
   644     Sets the username or UID used and optionally the groupname or GID for the specified command.
   645  
   646     The followings examples are all valid:
   647     --user [user | user:group | uid | uid:gid | user:gid | uid:group ]
   648  
   649     Without this argument the command will be run as root in the container.
   650  
   651  **--ulimit**=[]
   652      Ulimit options
   653  
   654  **-v**|**--volume**[=*[[HOST-DIR:]CONTAINER-DIR[:OPTIONS]]*]
   655     Create a bind mount. If you specify, ` -v /HOST-DIR:/CONTAINER-DIR`, Docker
   656     bind mounts `/HOST-DIR` in the host to `/CONTAINER-DIR` in the Docker
   657     container. If 'HOST-DIR' is omitted,  Docker automatically creates the new
   658     volume on the host.  The `OPTIONS` are a comma delimited list and can be:
   659  
   660     * [rw|ro]
   661     * [z|Z]
   662     * [`[r]shared`|`[r]slave`|`[r]private`]
   663     * [`delegated`|`cached`|`consistent`]
   664     * [nocopy]
   665  
   666  The `CONTAINER-DIR` must be an absolute path such as `/src/docs`. The `HOST-DIR`
   667  can be an absolute path or a `name` value. A `name` value must start with an
   668  alphanumeric character, followed by `a-z0-9`, `_` (underscore), `.` (period) or
   669  `-` (hyphen). An absolute path starts with a `/` (forward slash).
   670  
   671  If you supply a `HOST-DIR` that is an absolute path,  Docker bind-mounts to the
   672  path you specify. If you supply a `name`, Docker creates a named volume by that
   673  `name`. For example, you can specify either `/foo` or `foo` for a `HOST-DIR`
   674  value. If you supply the `/foo` value, Docker creates a bind mount. If you
   675  supply the `foo` specification, Docker creates a named volume.
   676  
   677  You can specify multiple  **-v** options to mount one or more mounts to a
   678  container. To use these same mounts in other containers, specify the
   679  **--volumes-from** option also.
   680  
   681  You can supply additional options for each bind mount following an additional
   682  colon.  A `:ro` or `:rw` suffix mounts a volume in read-only or read-write
   683  mode, respectively. By default, volumes are mounted in read-write mode.
   684  You can also specify the consistency requirement for the mount, either
   685  `:consistent` (the default), `:cached`, or `:delegated`.  Multiple options are
   686  separated by commas, e.g. `:ro,cached`.
   687  
   688  Labeling systems like SELinux require that proper labels are placed on volume
   689  content mounted into a container. Without a label, the security system might
   690  prevent the processes running inside the container from using the content. By
   691  default, Docker does not change the labels set by the OS.
   692  
   693  To change a label in the container context, you can add either of two suffixes
   694  `:z` or `:Z` to the volume mount. These suffixes tell Docker to relabel file
   695  objects on the shared volumes. The `z` option tells Docker that two containers
   696  share the volume content. As a result, Docker labels the content with a shared
   697  content label. Shared volume labels allow all containers to read/write content.
   698  The `Z` option tells Docker to label the content with a private unshared label.
   699  Only the current container can use a private volume.
   700  
   701  By default bind mounted volumes are `private`. That means any mounts done
   702  inside container will not be visible on host and vice-a-versa. One can change
   703  this behavior by specifying a volume mount propagation property. Making a
   704  volume `shared` mounts done under that volume inside container will be
   705  visible on host and vice-a-versa. Making a volume `slave` enables only one
   706  way mount propagation and that is mounts done on host under that volume
   707  will be visible inside container but not the other way around.
   708  
   709  To control mount propagation property of volume one can use `:[r]shared`,
   710  `:[r]slave` or `:[r]private` propagation flag. Propagation property can
   711  be specified only for bind mounted volumes and not for internal volumes or
   712  named volumes. For mount propagation to work source mount point (mount point
   713  where source dir is mounted on) has to have right propagation properties. For
   714  shared volumes, source mount point has to be shared. And for slave volumes,
   715  source mount has to be either shared or slave.
   716  
   717  Use `df <source-dir>` to figure out the source mount and then use
   718  `findmnt -o TARGET,PROPAGATION <source-mount-dir>` to figure out propagation
   719  properties of source mount. If `findmnt` utility is not available, then one
   720  can look at mount entry for source mount point in `/proc/self/mountinfo`. Look
   721  at `optional fields` and see if any propagation properties are specified.
   722  `shared:X` means mount is `shared`, `master:X` means mount is `slave` and if
   723  nothing is there that means mount is `private`.
   724  
   725  To change propagation properties of a mount point use `mount` command. For
   726  example, if one wants to bind mount source directory `/foo` one can do
   727  `mount --bind /foo /foo` and `mount --make-private --make-shared /foo`. This
   728  will convert /foo into a `shared` mount point. Alternatively one can directly
   729  change propagation properties of source mount. Say `/` is source mount for
   730  `/foo`, then use `mount --make-shared /` to convert `/` into a `shared` mount.
   731  
   732  > **Note**:
   733  > When using systemd to manage the Docker daemon's start and stop, in the systemd
   734  > unit file there is an option to control mount propagation for the Docker daemon
   735  > itself, called `MountFlags`. The value of this setting may cause Docker to not
   736  > see mount propagation changes made on the mount point. For example, if this value
   737  > is `slave`, you may not be able to use the `shared` or `rshared` propagation on
   738  > a volume.
   739  
   740  To disable automatic copying of data from the container path to the volume, use
   741  the `nocopy` flag. The `nocopy` flag can be set on bind mounts and named volumes.
   742  
   743  See also `--mount`, which is the successor of `--tmpfs` and `--volume`.
   744  Even though there is no plan to deprecate `--volume`, usage of `--mount` is recommended.
   745  
   746  **--volume-driver**=""
   747     Container's volume driver. This driver creates volumes specified either from
   748     a Dockerfile's `VOLUME` instruction or from the `docker run -v` flag.
   749     See **docker-volume-create(1)** for full details.
   750  
   751  **--volumes-from**=[]
   752     Mount volumes from the specified container(s)
   753  
   754     Mounts already mounted volumes from a source container onto another
   755     container. You must supply the source's container-id. To share
   756     a volume, use the **--volumes-from** option when running
   757     the target container. You can share volumes even if the source container
   758     is not running.
   759  
   760     By default, Docker mounts the volumes in the same mode (read-write or
   761     read-only) as it is mounted in the source container. Optionally, you
   762     can change this by suffixing the container-id with either the `:ro` or
   763     `:rw ` keyword.
   764  
   765     If the location of the volume from the source container overlaps with
   766     data residing on a target container, then the volume hides
   767     that data on the target.
   768  
   769  **-w**, **--workdir**=""
   770     Working directory inside the container
   771  
   772     The default working directory for
   773  running binaries within a container is the root directory (/). The developer can
   774  set a different default with the Dockerfile WORKDIR instruction. The operator
   775  can override the working directory by using the **-w** option.
   776  
   777  # Exit Status
   778  
   779  The exit code from `docker run` gives information about why the container
   780  failed to run or why it exited.  When `docker run` exits with a non-zero code,
   781  the exit codes follow the `chroot` standard, see below:
   782  
   783  **_125_** if the error is with Docker daemon **_itself_** 
   784  
   785      $ docker run --foo busybox; echo $?
   786      # flag provided but not defined: --foo
   787        See 'docker run --help'.
   788        125
   789  
   790  **_126_** if the **_contained command_** cannot be invoked
   791  
   792      $ docker run busybox /etc; echo $?
   793      # exec: "/etc": permission denied
   794        docker: Error response from daemon: Contained command could not be invoked
   795        126
   796  
   797  **_127_** if the **_contained command_** cannot be found
   798  
   799      $ docker run busybox foo; echo $?
   800      # exec: "foo": executable file not found in $PATH
   801        docker: Error response from daemon: Contained command not found or does not exist
   802        127
   803  
   804  **_Exit code_** of **_contained command_** otherwise 
   805      
   806      $ docker run busybox /bin/sh -c 'exit 3' 
   807      # 3
   808  
   809  # EXAMPLES
   810  
   811  ## Running container in read-only mode
   812  
   813  During container image development, containers often need to write to the image
   814  content.  Installing packages into /usr, for example.  In production,
   815  applications seldom need to write to the image.  Container applications write
   816  to volumes if they need to write to file systems at all.  Applications can be
   817  made more secure by running them in read-only mode using the --read-only switch.
   818  This protects the containers image from modification. Read only containers may
   819  still need to write temporary data.  The best way to handle this is to mount
   820  tmpfs directories on /run and /tmp.
   821  
   822      # docker run --read-only --tmpfs /run --tmpfs /tmp -i -t fedora /bin/bash
   823  
   824  ## Exposing log messages from the container to the host's log
   825  
   826  If you want messages that are logged in your container to show up in the host's
   827  syslog/journal then you should bind mount the /dev/log directory as follows.
   828  
   829      # docker run -v /dev/log:/dev/log -i -t fedora /bin/bash
   830  
   831  From inside the container you can test this by sending a message to the log.
   832  
   833      (bash)# logger "Hello from my container"
   834  
   835  Then exit and check the journal.
   836  
   837      # exit
   838  
   839      # journalctl -b | grep Hello
   840  
   841  This should list the message sent to logger.
   842  
   843  ## Attaching to one or more from STDIN, STDOUT, STDERR
   844  
   845  If you do not specify -a then Docker will attach everything (stdin,stdout,stderr)
   846  . You can specify to which of the three standard streams (stdin, stdout, stderr)
   847  you'd like to connect instead, as in:
   848  
   849      # docker run -a stdin -a stdout -i -t fedora /bin/bash
   850  
   851  ## Sharing IPC between containers
   852  
   853  Using shm_server.c available here: https://www.cs.cf.ac.uk/Dave/C/node27.html
   854  
   855  Testing `--ipc=host` mode:
   856  
   857  Host shows a shared memory segment with 7 pids attached, happens to be from httpd:
   858  
   859  ```
   860   $ sudo ipcs -m
   861  
   862   ------ Shared Memory Segments --------
   863   key        shmid      owner      perms      bytes      nattch     status      
   864   0x01128e25 0          root       600        1000       7                       
   865  ```
   866  
   867  Now run a regular container, and it correctly does NOT see the shared memory segment from the host:
   868  
   869  ```
   870   $ docker run -it shm ipcs -m
   871  
   872   ------ Shared Memory Segments --------
   873   key        shmid      owner      perms      bytes      nattch     status      
   874  ```
   875  
   876  Run a container with the new `--ipc=host` option, and it now sees the shared memory segment from the host httpd:
   877  
   878   ```
   879   $ docker run -it --ipc=host shm ipcs -m
   880  
   881   ------ Shared Memory Segments --------
   882   key        shmid      owner      perms      bytes      nattch     status      
   883   0x01128e25 0          root       600        1000       7                   
   884  ```
   885  Testing `--ipc=container:CONTAINERID` mode:
   886  
   887  Start a container with a program to create a shared memory segment:
   888  ```
   889   $ docker run -it shm bash
   890   $ sudo shm/shm_server &
   891   $ sudo ipcs -m
   892  
   893   ------ Shared Memory Segments --------
   894   key        shmid      owner      perms      bytes      nattch     status      
   895   0x0000162e 0          root       666        27         1                       
   896  ```
   897  Create a 2nd container correctly shows no shared memory segment from 1st container:
   898  ```
   899   $ docker run shm ipcs -m
   900  
   901   ------ Shared Memory Segments --------
   902   key        shmid      owner      perms      bytes      nattch     status      
   903  ```
   904  
   905  Create a 3rd container using the new --ipc=container:CONTAINERID option, now it shows the shared memory segment from the first:
   906  
   907  ```
   908   $ docker run -it --ipc=container:ed735b2264ac shm ipcs -m
   909   $ sudo ipcs -m
   910  
   911   ------ Shared Memory Segments --------
   912   key        shmid      owner      perms      bytes      nattch     status      
   913   0x0000162e 0          root       666        27         1
   914  ```
   915  
   916  ## Linking Containers
   917  
   918  > **Note**: This section describes linking between containers on the
   919  > default (bridge) network, also known as "legacy links". Using `--link`
   920  > on user-defined networks uses the DNS-based discovery, which does not add
   921  > entries to `/etc/hosts`, and does not set environment variables for
   922  > discovery.
   923  
   924  The link feature allows multiple containers to communicate with each other. For
   925  example, a container whose Dockerfile has exposed port 80 can be run and named
   926  as follows:
   927  
   928      # docker run --name=link-test -d -i -t fedora/httpd
   929  
   930  A second container, in this case called linker, can communicate with the httpd
   931  container, named link-test, by running with the **--link=<name>:<alias>**
   932  
   933      # docker run -t -i --link=link-test:lt --name=linker fedora /bin/bash
   934  
   935  Now the container linker is linked to container link-test with the alias lt.
   936  Running the **env** command in the linker container shows environment variables
   937   with the LT (alias) context (**LT_**)
   938  
   939      # env
   940      HOSTNAME=668231cb0978
   941      TERM=xterm
   942      LT_PORT_80_TCP=tcp://172.17.0.3:80
   943      LT_PORT_80_TCP_PORT=80
   944      LT_PORT_80_TCP_PROTO=tcp
   945      LT_PORT=tcp://172.17.0.3:80
   946      PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
   947      PWD=/
   948      LT_NAME=/linker/lt
   949      SHLVL=1
   950      HOME=/
   951      LT_PORT_80_TCP_ADDR=172.17.0.3
   952      _=/usr/bin/env
   953  
   954  When linking two containers Docker will use the exposed ports of the container
   955  to create a secure tunnel for the parent to access.
   956  
   957  If a container is connected to the default bridge network and `linked`
   958  with other containers, then the container's `/etc/hosts` file is updated
   959  with the linked container's name.
   960  
   961  > **Note** Since Docker may live update the container's `/etc/hosts` file, there
   962  may be situations when processes inside the container can end up reading an
   963  empty or incomplete `/etc/hosts` file. In most cases, retrying the read again
   964  should fix the problem.
   965  
   966  
   967  ## Mapping Ports for External Usage
   968  
   969  The exposed port of an application can be mapped to a host port using the **-p**
   970  flag. For example, an httpd port 80 can be mapped to the host port 8080 using the
   971  following:
   972  
   973      # docker run -p 8080:80 -d -i -t fedora/httpd
   974  
   975  ## Creating and Mounting a Data Volume Container
   976  
   977  Many applications require the sharing of persistent data across several
   978  containers. Docker allows you to create a Data Volume Container that other
   979  containers can mount from. For example, create a named container that contains
   980  directories /var/volume1 and /tmp/volume2. The image will need to contain these
   981  directories so a couple of RUN mkdir instructions might be required for you
   982  fedora-data image:
   983  
   984      # docker run --name=data -v /var/volume1 -v /tmp/volume2 -i -t fedora-data true
   985      # docker run --volumes-from=data --name=fedora-container1 -i -t fedora bash
   986  
   987  Multiple --volumes-from parameters will bring together multiple data volumes from
   988  multiple containers. And it's possible to mount the volumes that came from the
   989  DATA container in yet another container via the fedora-container1 intermediary
   990  container, allowing to abstract the actual data source from users of that data:
   991  
   992      # docker run --volumes-from=fedora-container1 --name=fedora-container2 -i -t fedora bash
   993  
   994  ## Mounting External Volumes
   995  
   996  To mount a host directory as a container volume, specify the absolute path to
   997  the directory and the absolute path for the container directory separated by a
   998  colon:
   999  
  1000      # docker run -v /var/db:/data1 -i -t fedora bash
  1001  
  1002  When using SELinux, be aware that the host has no knowledge of container SELinux
  1003  policy. Therefore, in the above example, if SELinux policy is enforced, the
  1004  `/var/db` directory is not writable to the container. A "Permission Denied"
  1005  message will occur and an avc: message in the host's syslog.
  1006  
  1007  
  1008  To work around this, at time of writing this man page, the following command
  1009  needs to be run in order for the proper SELinux policy type label to be attached
  1010  to the host directory:
  1011  
  1012      # chcon -Rt svirt_sandbox_file_t /var/db
  1013  
  1014  
  1015  Now, writing to the /data1 volume in the container will be allowed and the
  1016  changes will also be reflected on the host in /var/db.
  1017  
  1018  ## Using alternative security labeling
  1019  
  1020  You can override the default labeling scheme for each container by specifying
  1021  the `--security-opt` flag. For example, you can specify the MCS/MLS level, a
  1022  requirement for MLS systems. Specifying the level in the following command
  1023  allows you to share the same content between containers.
  1024  
  1025      # docker run --security-opt label=level:s0:c100,c200 -i -t fedora bash
  1026  
  1027  An MLS example might be:
  1028  
  1029      # docker run --security-opt label=level:TopSecret -i -t rhel7 bash
  1030  
  1031  To disable the security labeling for this container versus running with the
  1032  `--permissive` flag, use the following command:
  1033  
  1034      # docker run --security-opt label=disable -i -t fedora bash
  1035  
  1036  If you want a tighter security policy on the processes within a container,
  1037  you can specify an alternate type for the container. You could run a container
  1038  that is only allowed to listen on Apache ports by executing the following
  1039  command:
  1040  
  1041      # docker run --security-opt label=type:svirt_apache_t -i -t centos bash
  1042  
  1043  Note:
  1044  
  1045  You would have to write policy defining a `svirt_apache_t` type.
  1046  
  1047  ## Setting device weight
  1048  
  1049  If you want to set `/dev/sda` device weight to `200`, you can specify the device
  1050  weight by `--blkio-weight-device` flag. Use the following command:
  1051  
  1052      # docker run -it --blkio-weight-device "/dev/sda:200" ubuntu
  1053  
  1054  ## Specify isolation technology for container (--isolation)
  1055  
  1056  This option is useful in situations where you are running Docker containers on
  1057  Microsoft Windows. The `--isolation <value>` option sets a container's isolation
  1058  technology. On Linux, the only supported is the `default` option which uses
  1059  Linux namespaces. These two commands are equivalent on Linux:
  1060  
  1061  ```
  1062  $ docker run -d busybox top
  1063  $ docker run -d --isolation default busybox top
  1064  ```
  1065  
  1066  On Microsoft Windows, can take any of these values:
  1067  
  1068  * `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.
  1069  * `process`: Namespace isolation only.
  1070  * `hyperv`: Hyper-V hypervisor partition-based isolation.
  1071  
  1072  In practice, when running on Microsoft Windows without a `daemon` option set,  these two commands are equivalent:
  1073  
  1074  ```
  1075  $ docker run -d --isolation default busybox top
  1076  $ docker run -d --isolation process busybox top
  1077  ```
  1078  
  1079  If you have set the `--exec-opt isolation=hyperv` option on the Docker `daemon`, any of these commands also result in `hyperv` isolation:
  1080  
  1081  ```
  1082  $ docker run -d --isolation default busybox top
  1083  $ docker run -d --isolation hyperv busybox top
  1084  ```
  1085  
  1086  ## Setting Namespaced Kernel Parameters (Sysctls)
  1087  
  1088  The `--sysctl` sets namespaced kernel parameters (sysctls) in the
  1089  container. For example, to turn on IP forwarding in the containers
  1090  network namespace, run this command:
  1091  
  1092      $ docker run --sysctl net.ipv4.ip_forward=1 someimage
  1093  
  1094  Note:
  1095  
  1096  Not all sysctls are namespaced. Docker does not support changing sysctls
  1097  inside of a container that also modify the host system. As the kernel 
  1098  evolves we expect to see more sysctls become namespaced.
  1099  
  1100  See the definition of the `--sysctl` option above for the current list of 
  1101  supported sysctls.
  1102  
  1103  # HISTORY
  1104  April 2014, Originally compiled by William Henry (whenry at redhat dot com)
  1105  based on docker.com source material and internal work.
  1106  June 2014, updated by Sven Dowideit <SvenDowideit@home.org.au>
  1107  July 2014, updated by Sven Dowideit <SvenDowideit@home.org.au>
  1108  November 2015, updated by Sally O'Malley <somalley@redhat.com>