Multus is the latin word for “Multi”
As name suggest, it act as the Multi plugin in the Kubernetes and provides the Multi interface support in pod
It is generic to run with other plugins like ptp, local-host, calico and flannel, with different IPAM and networks.
It contact between the container runtime and other plugins, and it isn't having any of it own net configuration, it call other plugins like flannel/calico to do the real net conf job.
Multus reuse the concept of invoking the delegates in the flannel, it group the multi plugins into delegates and invoke each other in the sequential order, according to the JSON scheme in the cni configuration.

Build

This plugin requires Go 1.5+ to build.

Go 1.5 users will need to set GO15VENDOREXPERIMENT=1 to get vendored dependencies. This flag is set by default in 1.6.

#./build

Network configuration reference

name (string, required): the name of the network
type (string, required): "multus"
delegate (([]map,required): number of delegate details in the Multus
masterplugin (bool,required): master plugin to report back to container

Usage

Given the following network configuration:

# tee /etc/cni/net.d/multus-cni.conf <<-'EOF'
{
    "name": "minion1-multus-demo-network",
    "type": "multus",
    "delegates": [
        {
                "type": "sriov",
                "if0": "enp12s0f0",
                "if0name": "north0",
                "createmac": true,
                "ipam": {
                        "type": "host-local",
                        "subnet": "10.56.217.0/24",
                        "rangeStart": "10.56.217.131",
                        "rangeEnd": "10.56.217.190",
                        "routes": [
                                { "dst": "0.0.0.0/0" }
                        ],
                        "gateway": "10.56.217.1"
                }
        },
        {
                "type": "sriov",
                "if0": "enp12s0f1",
                "if0name": "south0",
                "ipam": {
                        "type": "host-local",
                        "subnet": "10.56.217.0/24",
                        "rangeStart": "10.56.217.100",
                        "rangeEnd": "10.56.217.130",
                        "routes": [
                                { "dst": "0.0.0.0/0" }
                        ],
                        "gateway": "10.56.217.1"
                }
        },
        {
                "type": "flannel",
                "masterplugin": true,
                "delegate": {
                        "isDefaultGateway": true
                }
        }
    ]
}
EOF

Testing the Multus CNI with docker

Make sure that the multus, sriov and flannel binaries are in the /opt/cni/bin directories and follow the steps as mention in the CNI