github.com/sijibomii/docker@v0.0.0-20231230191044-5cf6ca554647/docs/reference/commandline/network_create.md (about)

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     3  title = "network create"
     4  description = "The network create command description and usage"
     5  keywords = ["network, create"]
     6  [menu.main]
     7  parent = "smn_cli"
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     9  <![end-metadata]-->
    10  
    11  # network create
    12  
    13      Usage:  docker network create [OPTIONS] NETWORK-NAME
    14  
    15      Creates a new network with a name specified by the user
    16  
    17      --aux-address=map[]      Auxiliary ipv4 or ipv6 addresses used by network driver
    18      -d --driver=DRIVER       Driver to manage the Network bridge or overlay. The default is bridge.
    19      --gateway=[]             ipv4 or ipv6 Gateway for the master subnet
    20      --help                   Print usage
    21      --internal               Restricts external access to the network
    22      --ip-range=[]            Allocate container ip from a sub-range
    23      --ipam-driver=default    IP Address Management Driver
    24      --ipam-opt=map[]         Set custom IPAM driver specific options
    25      --ipv6                   Enable IPv6 networking
    26      --label=[]               Set metadata on a network
    27      -o --opt=map[]           Set custom driver specific options
    28      --subnet=[]              Subnet in CIDR format that represents a network segment
    29  
    30  Creates a new network. The `DRIVER` accepts `bridge` or `overlay` which are the
    31  built-in network drivers. If you have installed a third party or your own custom
    32  network driver you can specify that `DRIVER` here also. If you don't specify the
    33  `--driver` option, the command automatically creates a `bridge` network for you.
    34  When you install Docker Engine it creates a `bridge` network automatically. This
    35  network corresponds to the `docker0` bridge that Engine has traditionally relied
    36  on. When launch a new container with  `docker run` it automatically connects to
    37  this bridge network. You cannot remove this default bridge network but you can
    38  create new ones using the `network create` command.
    39  
    40  ```bash
    41  $ docker network create -d bridge my-bridge-network
    42  ```
    43  
    44  Bridge networks are isolated networks on a single Engine installation. If you
    45  want to create a network that spans multiple Docker hosts each running an
    46  Engine, you must create an `overlay` network. Unlike `bridge` networks overlay
    47  networks require some pre-existing conditions before you can create one. These
    48  conditions are:
    49  
    50  * Access to a key-value store. Engine supports Consul, Etcd, and ZooKeeper (Distributed store) key-value stores.
    51  * A cluster of hosts with connectivity to the key-value store.
    52  * A properly configured Engine `daemon` on each host in the cluster.
    53  
    54  The `docker daemon` options that support the `overlay` network are:
    55  
    56  * `--cluster-store`
    57  * `--cluster-store-opt`
    58  * `--cluster-advertise`
    59  
    60  To read more about these options and how to configure them, see ["*Get started
    61  with multi-host network*"](../../userguide/networking/get-started-overlay.md).
    62  
    63  It is also a good idea, though not required, that you install Docker Swarm on to
    64  manage the cluster that makes up your network. Swarm provides sophisticated
    65  discovery and server management that can assist your implementation.
    66  
    67  Once you have prepared the `overlay` network prerequisites you simply choose a
    68  Docker host in the cluster and issue the following to create the network:
    69  
    70  ```bash
    71  $ docker network create -d overlay my-multihost-network
    72  ```
    73  
    74  Network names must be unique. The Docker daemon attempts to identify naming
    75  conflicts but this is not guaranteed. It is the user's responsibility to avoid
    76  name conflicts.
    77  
    78  ## Connect containers
    79  
    80  When you start a container use the `--net` flag to connect it to a network.
    81  This adds the `busybox` container to the `mynet` network.
    82  
    83  ```bash
    84  $ docker run -itd --net=mynet busybox
    85  ```
    86  
    87  If you want to add a container to a network after the container is already
    88  running use the `docker network connect` subcommand.
    89  
    90  You can connect multiple containers to the same network. Once connected, the
    91  containers can communicate using only another container's IP address or name.
    92  For `overlay` networks or custom plugins that support multi-host connectivity,
    93  containers connected to the same multi-host network but launched from different
    94  Engines can also communicate in this way.
    95  
    96  You can disconnect a container from a network using the `docker network
    97  disconnect` command.
    98  
    99  ## Specifying advanced options
   100  
   101  When you create a network, Engine creates a non-overlapping subnetwork for the network by default. This subnetwork is not a subdivision of an existing network. It is purely for ip-addressing purposes. You can override this default and specify subnetwork values directly using the `--subnet` option. On a `bridge` network you can only create a single subnet:
   102  
   103  ```bash
   104  docker network create -d --subnet=192.168.0.0/16
   105  ```
   106  Additionally, you also specify the `--gateway` `--ip-range` and `--aux-address` options.
   107  
   108  ```bash
   109  network create --driver=bridge --subnet=172.28.0.0/16 --ip-range=172.28.5.0/24 --gateway=172.28.5.254 br0
   110  ```
   111  
   112  If you omit the `--gateway` flag the Engine selects one for you from inside a
   113  preferred pool. For `overlay` networks and for network driver plugins that
   114  support it you can create multiple subnetworks.
   115  
   116  ```bash
   117  docker network create -d overlay
   118    --subnet=192.168.0.0/16 --subnet=192.170.0.0/16
   119    --gateway=192.168.0.100 --gateway=192.170.0.100
   120    --ip-range=192.168.1.0/24
   121    --aux-address a=192.168.1.5 --aux-address b=192.168.1.6
   122    --aux-address a=192.170.1.5 --aux-address b=192.170.1.6
   123    my-multihost-network
   124  ```
   125  Be sure that your subnetworks do not overlap. If they do, the network create fails and Engine returns an error.
   126  
   127  # Bridge driver options
   128  
   129  When creating a custom network, the default network driver (i.e. `bridge`) has additional options that can be passed.
   130  The following are those options and the equivalent docker daemon flags used for docker0 bridge:
   131  
   132  | Option                                           | Equivalent  | Description                                           |
   133  |--------------------------------------------------|-------------|-------------------------------------------------------|
   134  | `com.docker.network.bridge.name`                 | -           | bridge name to be used when creating the Linux bridge |
   135  | `com.docker.network.bridge.enable_ip_masquerade` | `--ip-masq` | Enable IP masquerading                                |
   136  | `com.docker.network.bridge.enable_icc`           | `--icc`     | Enable or Disable Inter Container Connectivity        |
   137  | `com.docker.network.bridge.host_binding_ipv4`    | `--ip`      | Default IP when binding container ports               |
   138  | `com.docker.network.mtu`                         | `--mtu`     | Set the containers network MTU                        |
   139  
   140  The following arguments can be passed to `docker network create` for any network driver, again with their approximate
   141  equivalents to `docker daemon`.
   142  
   143  | Argument     | Equivalent     | Description                                |
   144  |--------------|----------------|--------------------------------------------|
   145  | `--gateway`  | -              | ipv4 or ipv6 Gateway for the master subnet |
   146  | `--ip-range` | `--fixed-cidr` | Allocate IPs from a range                  |
   147  | `--internal` | -              | Restricts external access to the network   |
   148  | `--ipv6`     | `--ipv6`       | Enable IPv6 networking                     |
   149  | `--subnet`   | `--bip`        | Subnet for network                         |
   150  
   151  For example, let's use `-o` or `--opt` options to specify an IP address binding when publishing ports:
   152  
   153  ```bash
   154  docker network create -o "com.docker.network.bridge.host_binding_ipv4"="172.19.0.1" simple-network
   155  ```
   156  
   157  ### Network internal mode
   158  
   159  By default, when you connect a container to an `overlay` network, Docker also connects a bridge network to it to provide external connectivity.
   160  If you want to create an externally isolated `overlay` network, you can specify the `--internal` option.
   161  
   162  ## Related information
   163  
   164  * [network inspect](network_inspect.md)
   165  * [network connect](network_connect.md)
   166  * [network disconnect](network_disconnect.md)
   167  * [network ls](network_ls.md)
   168  * [network rm](network_rm.md)
   169  * [Understand Docker container networks](../../userguide/networking/dockernetworks.md)