Creating and inspecting a network

Let's create a network. We are going to call our network myNetwork. Execute the following command from the shell or command line:

$ docker network create myNetwork  

This is the simplest form of the command, and yet it will probably be used the most often. It takes a default driver (we haven't used any option to specify a driver, we will just use the default one, which is bridge). As the output, Docker will print out the identifier of the newly created network:

You will later use this identifier to refer to this network when connecting containers to it or inspecting the network's properties. The last parameter of the command is the network's name, which is a lot more convenient and easier to remember than the ID. The network name in our case is myNetwork. The docker network create command takes more parameters, as shown in the following table:

Option

Description

-d, -driver="bridge"

Driver to manage the network

-aux-address=map[]

Auxiliary IPv4 or IPv6 addresses used by network driver

-gateway=[]

IPv4 or IPv6 gateway for the master subnet

-ip-range=[]

Allocate container IP from a sub-range

-ipam-driver=default

IP address management driver

-o, -opt=map[]

Set driver's specific options

-subnet=[]

Subnet in CIDR format that represents a network segment

One of the most important parameters is the -d (--driver) option, with the default value bridge. Drivers let you specify the network type. As you remember, Docker has a couple of drivers available by default: host, bridge, and none.

After creating a network, we can inspect its properties using the docker network inspect command. Execute the following from the shell or command line:

$ docker network inspect myNetwork 

In response, you will get a lot of detailed information about your network. As you can see in the screenshot, our newly created network uses the bridge driver, even if we haven't explicitly asked for it:

As you can see, the container list is empty, and the reason why is that we haven't connected any container to this network yet. Let's do it now.