node-ipam-controller

Out of tree implementation of https://github.com/kubernetes/enhancements/tree/master/keps/sig-network/2593-multiple-cluster-cidrs

It allows users to use an ipam-controller that allocates IP ranges to Nodes, setting the node.spec.PodCIDRs fields. The ipam-controller is configured via CRDs

Config

Command line	Environment	Default	Description
apiserver	IPAM_API_SERVER_URL		The address of the Kubernetes API server. Overrides any value in kubeconfig. Only required if out-of-cluster.
kubeconfig	IPAM_KUBECONFIG		Path to a kubeconfig. Only required if out-of-cluster.
health-probe-address	IPAM_HEALTH_PROBE_ADDR	:8081	Specifies the TCP address for the health server to listen on.
enable-leader-election	IPAM_ENABLE_LEADER_ELECTION	true	Enable leader election for the controller manager. Ensures there is only one active controller manager.
leader-elect-lease-duration	IPAM_LEASE_DURATION	15s	Duration that non-leader candidates will wait to force acquire leadership (duration string).
leader-elect-renew-deadline	IPAM_RENEW_DEADLINE	10s	Interval between attempts by the acting master to renew a leadership slot before it stops leading (duration string).
leader-elect-retry-period	IPAM_RESOURCE_LOCK	2s	Duration the clients should wait between attempting acquisition and renewal of a leadership (duration string).
leader-elect-resource-lock	IPAM_RESOURCE_LOCK_NAME	leases	The type of resource object that is used for locking. Supported options are 'leases', 'endpoints', 'configmaps'.
leader-elect-resource-name	IPAM_RESOURCE_NAME	node-ipam-controller	The name of the resource object that is used for locking.

Build

To build the binary for node-ipam-controller:

make build

To build the Docker image for node-ipam-controller:

make image-build

Run

Create a Kind cluster with disabled Node CIDRs allocation:

kind create cluster --config hack/test/kind/kind-cfg.yaml

Install ClusterCIDR CRD and configure node-ipam-controller to use dual mode (See the examples folder for more examples):

kubectl create -f charts/node-ipam-controller/gen/crds/networking.x-k8s.io_clustercidrs.yaml
kubectl create -f examples/clustercidr-dual.yaml

Run the controller outside the cluster by specifying Kind cluster kubeconfig:

./bin/manager --kubeconfig="$HOME"/.kube/config

To run the controller inside the cluster, a Docker image must first be loaded into a registry accessible within the Kind cluster.

docker build -t registry.k8s.io/node-ipam-controller/node-ipam-controller:local -f Dockerfile .
docker save --output node-ipam-controller.tar registry.k8s.io/node-ipam-controller/node-ipam-controller:local
kind load docker-image registry.k8s.io/node-ipam-controller/node-ipam-controller:local

Check Kind documentation on how to use local container image registry.

Install node-ipam-controller in the cluster via helm:

helm install node-ipam-controller ./charts/node-ipam-controller --create-namespace --namespace nodeipam --set image.tag=local