This repo is for examples of a plugin w/ libnetwork and temporary until we get Ipvlan/Macvlan native driver support in Docker which will be relatively soon. This will deprecate in order to focus on much more interesting Gopher networking scenarios like integrations. While it can be supported here, the effort would be kind of wasted since we will get it native soon so hang tight for trunks.

Macvlan is a lightweight bridgless implementation that can be ideal for some scenarios that fit simple network needs with vlans and 802.1q trunks.

The kernel dependency is the macvlan kernel module support. You can verify if you have it compiled in or not with the following:

$ modprobe macvlan
$ lsmod | grep macvlan
  macvlan   24576  0

If you get any errors or it doesn't show up from lsmod then you probably need to simply upgrade the kernel version. Here is an example upgrade to v4.3-rc2 that works on both Ubuntu 15.04 and 14.10 along with the similar Debian distributions.

$ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.3-rc2-unstable/linux-headers-4.3.0-040300rc2_4.3.0-040300rc2.201509201830_all.deb
$ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.3-rc2-unstable/linux-headers-4.3.0-040300rc2-generic_4.3.0-040300rc2.201509201830_amd64.deb
$ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.3-rc2-unstable/linux-image-4.3.0-040300rc2-generic_4.3.0-040300rc2.201509201830_amd64.deb
$ dpkg -i linux-headers-4.3*.deb linux-image-4.3*.deb
$ reboot

As of Docker v1.9 the docker/libnetwork APIs are packaged by default in Docker. Grab the latest or v1.9+ version of Docker from Latest Linux binary from Docker. Alternatively curl -sSL https://get.docker.com/ | sh or from your distribution repo or docker repos.

This example is also available in a screencast on youtube.

To see verbose output please see this gist.

1. Start Docker with the following or simply start the service. Version 1.9+ is required for 3rd party external network plugins.

$ docker -v
Docker version 1.9.1, build a34a1d5

# -D is optional debugging
$ docker daemon -D

2. Start the driver in bridge mode.

Either using Docker:

$ docker run -d --privileged --net host \
    -v /usr/share/docker/plugins/macvlan.sock:/usr/share/docker/plugins/macvlan.sock \
    -v /var/run/docker.sock:/var/run/docker.sock \
    gophernet/macvlan-plugin

Or using docker-compose:

$ git clone github.com/gopher-net/macvlan-docker-plugin
$ vi docker-compose.yml
$ docker-compose up -d

To enable debugging, add -d to the docker run command or add command: -d to docker-compose.yml

3. Create a network with Docker

Note the subnet needs to correspond to the master interface. In this example, the nic eth1 is attached to a subnet 192.168.1.0/24. The container needs to be on the same broadast domain as the default gateway. In this case it is a router with the address of 192.168.1.1.

$ docker network create -d macvlan --subnet=192.168.1.0/24 --gateway=192.168.1.1 -o host_iface=eth1 net1

4. Run some containers on the new network

Run some containers, specify the network and verify they can ping one another

$ docker run --net=net1 -it --rm debian

Docker networks are now persistant after a reboot. The plugin does not currently support dealing with unknown networks. That is a priority next. To remove all of the network configs on a docker daemon restart you can simply delete the directory with: rm /var/lib/docker/network/files/*

Note Containers using the same parent interface e.g. eth1.20 can reach one another without an external router (intra-vlan). Containers on different VLANs/parent interfaces can not reach one another without an external router (inter-vlan).

# create a new subinterface tied to dot1q vlan 20
   ip link add link eth1 name eth1.20 type vlan id 20

# enable the new sub-interface
   ip link set eth1.20 up

# now add networks and hosts as you would normally by attaching to the master (sub)interface that is tagged
   docker network  create  -d macvlan  --subnet=192.168.20.0/24 --gateway=192.168.20.1 -o host_iface=eth1.20 macvlan20
   docker run --net=macvlan20 -it --name mcv_test1 --rm debian
   docker run --net=macvlan20 -it --name mcv_test2 --rm debian

# mcv_test1 should be able to ping mcv_test2 now.

# create a new subinterface tied to dot1q vlan 30
   ip link add link eth1 name eth1.30 type vlan id 30

# enable the new sub-interface
   ip link set eth1.30 up

# now add networks and hosts as you would normally by attaching to the master (sub)interface that is tagged
   docker network  create  -d macvlan  --subnet=192.168.30.0/24 --gateway=192.168.30.1 -o host_iface=eth1.30 macvlan30
   docker run --net=macvlan30 -it --name mcv_test3 --rm debian
   docker run --net=macvlan30 -it --name mcv_test4 --rm debian

# mcv_test3 should be able to ping mcv_test4 now.

• There can only be one network type bound to the host interface at any given time. Example: Macvlan Bridge or IPVlan L2. There is no mixing.
• The specified gateway is external to the host or at least not defined by the driver itself.
• Multiple drivers can be active at any time. However, Macvlan and Ipvlan are not compatable on the same master interface (e.g. eth0).
• You can create multiple networks and have active containers in each network as long as they are all of the same mode type.
• Each network is isolated from one another. Any container inside the network/subnet can talk to one another without a reachable gateway.
• Containers on separate networks cannot reach one another without an external process routing between the two networks/subnets.

To run the plugin via Go for hacking simply run go with the main.go. The same applies to the gopher-net/ipvlan driver:

go run main.go -d

Use Godep for dependencies.

Install and use Godep with the following:

$ go get github.com/tools/godep
# From inside the plugin directory where the Godep directory is restore the snapshotted dependencies used by libnetwork:
$ godep restore

There is a godbus/dbus version that conflicts with vishvananda/netlink that will lead to this error at build time. This can appear as libnetwork issues when in fact it is 3rd party drivers. Libnetwork also uses Godep for versioning so using those versions would be just as good or even better if keeping with the latest experimental nightly Docker builds:

Example of the godbus error:

../../../docker/libnetwork/iptables/firewalld.go:75: cannot use c.sysconn.Object(dbusInterface, dbus.ObjectPath(dbusPath)) (type dbus.BusObject) as type *dbus.
Object in assignment: need type assertion

• If you dont want to use godep @Orivej graciously pointed out the godbus dependency in issue #5:

"You need a stable godbus that you can probably get with:"

cd $GOPATH/src/github.com/godbus/dbus
git checkout v2

• Another option would be to use godep and sync your library with libnetworks.

go get github.com/tools/godep
git clone https://github.com/docker/libnetwork.git
cd libnetwork
godep restore