DockerCLI/experimental/networking.md

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# Experimental: Networking and Services
In this feature:
- `network` and `service` become first class objects in the Docker UI
- one can now create networks, publish services on that network and attach containers to the services
- Native multi-host networking
- `network` and `service` objects are globally significant and provides multi-host container connectivity natively
- Inbuilt simple Service Discovery
- With multi-host networking and top-level `service` object, Docker now provides out of the box simple Service Discovery for containers running in a network
- Batteries included but removable
- Docker provides inbuilt native multi-host networking by default & can be swapped by any remote driver provided by external plugins.
This is an experimental feature. For information on installing and using experimental features, see [the experimental feature overview](README.md).
## Using Networks
Usage: docker network [OPTIONS] COMMAND [OPTIONS] [arg...]
Commands:
create Create a network
rm Remove a network
ls List all networks
info Display information of a network
Run 'docker network COMMAND --help' for more information on a command.
--help=false Print usage
The `docker network` command is used to manage Networks.
To create a network, `docker network create foo`. You can also specify a driver
if you have loaded a networking plugin e.g `docker network create -d <plugin_name> foo`
$ docker network create foo
aae601f43744bc1f57c515a16c8c7c4989a2cad577978a32e6910b799a6bccf6
$ docker network create -d overlay bar
d9989793e2f5fe400a58ef77f706d03f668219688ee989ea68ea78b990fa2406
`docker network ls` is used to display the currently configured networks
$ docker network ls
NETWORK ID NAME TYPE
d367e613ff7f none null
bd61375b6993 host host
cc455abccfeb bridge bridge
aae601f43744 foo bridge
d9989793e2f5 bar overlay
To get detailed information on a network, you can use the `docker network info`
command.
$ docker network info foo
Network Id: aae601f43744bc1f57c515a16c8c7c4989a2cad577978a32e6910b799a6bccf6
Name: foo
Type: null
If you no longer have need of a network, you can delete it with `docker network rm`
$ docker network rm bar
bar
$ docker network ls
NETWORK ID NAME TYPE
aae601f43744 foo bridge
d367e613ff7f none null
bd61375b6993 host host
cc455abccfeb bridge bridge
## User-Defined default network
Docker daemon supports a configuration flag `--default-network` which takes configuration value of format `DRIVER:NETWORK`, where,
`DRIVER` represents the in-built drivers such as bridge, overlay, container, host and none. or Remote drivers via Network Plugins.
`NETWORK` is the name of the network created using the `docker network create` command
When a container is created and if the network mode (`--net`) is not specified, then this default network will be used to connect
the container. If `--default-network` is not specified, the default network will be the `bridge` driver.
Example : `docker -d --default-network=overlay:multihost`
## Using Services
Usage: docker service COMMAND [OPTIONS] [arg...]
Commands:
publish Publish a service
unpublish Remove a service
attach Attach a backend (container) to the service
detach Detach the backend from the service
ls Lists all services
info Display information about a service
Run 'docker service COMMAND --help' for more information on a command.
--help=false Print usage
Assuming we want to publish a service from container `a0ebc12d3e48` on network `foo` as `my-service` we would use the following command:
$ docker service publish my-service.foo
ec56fd74717d00f968c26675c9a77707e49ae64b8e54832ebf78888eb116e428
$ docker service attach a0ebc12d3e48 my-service.foo
This would make the container `a0ebc12d3e48` accessible as `my-service` on network `foo`. Any other container in network `foo` can use DNS to resolve the address of `my-service`
This can also be acheived by using the `--publish-service` flag for `docker run`:
docker run -itd --publish-service db.foo postgres
`db.foo` in this instance means "place the container on network `foo`, and allow other hosts on `foo` to discover it under the name `db`"
We can see the current services using the `docker service ls` command
$ docker service ls
SERVICE ID NAME NETWORK PROVIDER
ec56fd74717d my-service foo a0ebc12d3e48
To remove the a service:
$ docker service detach a0ebc12d3e48 my-service.foo
$ docker service unpublish my-service.foo
## Native Multi-host networking
There is a lot to talk about the native multi-host networking and the `overlay` driver that makes it happen. The technical details are documented under https://github.com/docker/libnetwork/blob/master/docs/overlay.md.
Using the above experimental UI `docker network`, `docker service` and `--publish-service`, the user can exercise the power of multi-host networking.
Since `network` and `service` objects are globally significant, this feature requires distributed states provided by the `libkv` project.
Using `libkv`, the user can plug any of the supported Key-Value store (such as consul, etcd or zookeeper).
User can specify the Key-Value store of choice using the `--kv-store` daemon flag, which takes configuration value of format `PROVIDER:URL`, where
`PROVIDER` is the name of the Key-Value store (such as consul, etcd or zookeeper) and
`URL` is the url to reach the Key-Value store.
Example : `docker -d --kv-store=consul:localhost:8500`
Send us feedback and comments on [#14083](https://github.com/docker/docker/issues/14083)
or on the usual Google Groups (docker-user, docker-dev) and IRC channels.