github.com/45cali/docker@v1.11.1/docs/reference/commandline/network_create.md (about) 1 <!--[metadata]> 2 +++ 3 title = "network create" 4 description = "The network create command description and usage" 5 keywords = ["network, create"] 6 [menu.main] 7 parent = "smn_cli" 8 +++ 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)