Weave network driver extension for Docker

A plugin to integrate weave Net with Docker.

Setup:

Before you can use this plugin, you must install weave and configure docker with a "cluster store".

$ weave launch
$ weave launch-plugin
$ docker network create --driver=weave weave

Starting a container:

$ docker run --net=weave -ti ubuntu

Plugin command-line arguments

• --socket=<path>, which is the socket on which to listen for the plugin protocol. This defaults to what Docker expects, that is "/run/docker/plugins/weave.sock", but you may wish to change it, for instance if you're running more than one instance of the driver for some reason.

• --log-level=debug|info|warning|error, which tells the plugin how much information to emit for debugging.

Points to note

Network plugins require Docker version 1.9 or later.

Docker needs a "cluster store"

Weave operates as a "globally scoped" libnetwork driver, which means libnetwork will assume all networks and endpoints are commonly known to all hosts. It does this by using a shared database which you must provide.

As a consequence, you need to supply Docker with the address of a "cluster store" when you start it; for example, an etcd installation.

There's no specific documentation for using a cluster store, but the first part of this guide may help.

WeaveDNS not supported

Weave's built-in service discovery mechanism is not currently supported by the plugin. However, Docker provides a rudimentary discovery mechanism by writing all user-provided container names and hostnames into every container's /etc/hosts.

Restarting

We start the plugin with a restart policy of 'always', because Docker attempts to recreate networks on startup which means the plugin container has to be started. If it isn't started automatically by Docker with a restart policy, it's not possible to start it manually because Docker is blocked.

Building (for developers)

make

You will need the same setup as the weave repository needs; easiest is to use the Vagrantfile in there and add another shared folder for this directory.