% DOCKER(1) Docker User Manuals % Docker Community % OCT 2015
docker-network-create - create a new network
docker network create [--attachable] [--aux-address=map] [-d|--driver=DRIVER] [--gateway=] [--help] [--internal] [--ip-range=] [--ipam-driver=default] [--ipam-opt=map] [--ipv6] [--label[=]] [-o|--opt=map] [--subnet=] NETWORK-NAME
Creates a new network. The
overlay which are the built-in network drivers. If you have installed a third party or your own custom network driver you can specify that
DRIVER here also. If you don't specify the
--driver option, the command automatically creates a
bridge network for you. When you install Docker Engine it creates a
bridge network automatically. This network corresponds to the
docker0 bridge that Engine has traditionally relied on. When launch a new container with
docker run it automatically connects to this bridge network. You cannot remove this default bridge network but you can create new ones using the
network create command.
$ docker network create -d bridge my-bridge-network
Bridge networks are isolated networks on a single Engine installation. If you want to create a network that spans multiple Docker hosts each running an Engine, you must create an
overlay network. Unlike
bridge networks overlay networks require some pre-existing conditions before you can create one. These conditions are:
daemonon each host in the cluster.
dockerd options that support the
overlay network are:
To read more about these options and how to configure them, see “Get started with multi-host network”.
It is also a good idea, though not required, that you install Docker Swarm on to manage the cluster that makes up your network. Swarm provides sophisticated discovery and server management that can assist your implementation.
Once you have prepared the
overlay network prerequisites you simply choose a Docker host in the cluster and issue the following to create the network:
$ docker network create -d overlay my-multihost-network
Network names must be unique. The Docker daemon attempts to identify naming conflicts but this is not guaranteed. It is the user's responsibility to avoid name conflicts.
When you start a container use the
--network flag to connect it to a network. This adds the
busybox container to the
$ docker run -itd --network=mynet busybox
If you want to add a container to a network after the container is already running use the
docker network connect subcommand.
You can connect multiple containers to the same network. Once connected, the containers can communicate using only another container's IP address or name. For
overlay networks or custom plugins that support multi-host connectivity, containers connected to the same multi-host network but launched from different Engines can also communicate in this way.
You can disconnect a container from a network using the
docker network disconnect command.
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:
$ docker network create -d bridge --subnet=192.168.0.0/16 br0
Additionally, you also specify the
$ docker network create \ --driver=bridge \ --subnet=172.28.0.0/16 \ --ip-range=172.28.5.0/24 \ --gateway=172.28.5.254 \ br0
If you omit the
--gateway flag the Engine selects one for you from inside a preferred pool. For
overlay networks and for network driver plugins that support it you can create multiple subnetworks.
$ docker network create -d overlay \ --subnet=192.168.0.0/16 \ --subnet=220.127.116.11/16 \ --gateway=192.168.0.100 \ --gateway=18.104.22.168 \ --ip-range=192.168.1.0/24 \ --aux-address="my-router=192.168.1.5" --aux-address="my-switch=192.168.1.6" \ --aux-address="my-printer=22.214.171.124" --aux-address="my-nas=126.96.36.199" \ my-multihost-network
Be sure that your subnetworks do not overlap. If they do, the network create fails and Engine returns an error.
By default, when you connect a container to an
overlay network, Docker also connects a bridge network to it to provide external connectivity. If you want to create an externally isolated
overlay network, you can specify the
--attachable Enable manual container attachment
--aux-address=map Auxiliary IPv4 or IPv6 addresses used by network driver
-d, --driver=DRIVER Driver to manage the Network bridge or overlay. The default is bridge.
--gateway= IPv4 or IPv6 Gateway for the master subnet
--help Print usage
--internal Restrict external access to the network
--ip-range= Allocate container ip from a sub-range
--ipam-driver=default IP Address Management Driver
--ipam-opt=map Set custom IPAM driver options
--ipv6 Enable IPv6 networking
--label=label Set metadata for a network
-o, --opt=map Set custom driver options
--subnet= Subnet in CIDR format that represents a network segment
OCT 2015, created by Mary Anthony email@example.com