Automatically apply CNI on multinode clusters

cmd/minikube/cmd/node_add.go

@@ -61,6 +61,12 @@ var nodeAddCmd = &cobra.Command{
 			}
 		}
 
+		// Add CNI config if it's not already there
+		// We need to run kubeadm.init here as well
+		if err := config.MultiNodeCNIConfig(cc); err != nil {
+			exit.WithError("failed to save config", err)
+		}
+
 		out.T(out.Ready, "Successfully added {{.name}} to {{.cluster}}!", out.V{"name": name, "cluster": cc.Name})
 	},
 }

pkg/drivers/kic/types.go

@@ -23,12 +23,6 @@ import (
 )
 
 const (
-	// DefaultNetwork is the Docker default bridge network named "bridge"
-	// (https://docs.docker.com/network/bridge/#use-the-default-bridge-network)
-	DefaultNetwork = "bridge"
-	// DefaultPodCIDR is The CIDR to be used for pods inside the node.
-	DefaultPodCIDR = "10.244.0.0/16"
-
 	// Version is the current version of kic
 	Version = "v0.0.9"
 	// SHA of the kic base image

pkg/minikube/bootstrapper/kubeadm/kubeadm.go

@@ -226,7 +226,7 @@ func (k *Bootstrapper) init(cfg config.ClusterConfig) error {
 			glog.Errorf("unable to create cluster role binding, some addons might not work: %v", err)
 		}
 		// the overlay is required for containerd and cri-o runtime: see #7428
-		if driver.IsKIC(cfg.Driver) && cfg.KubernetesConfig.ContainerRuntime != "docker" {
+		if config.MultiNode(cfg) || (driver.IsKIC(cfg.Driver) && cfg.KubernetesConfig.ContainerRuntime != "docker") {
 			if err := k.applyKICOverlay(cfg); err != nil {
 				glog.Errorf("failed to apply kic overlay: %v", err)
 			}

pkg/minikube/cluster/cluster.go

@@ -28,7 +28,9 @@ import (
 	"k8s.io/minikube/pkg/minikube/bootstrapper/kubeadm"
 	"k8s.io/minikube/pkg/minikube/command"
 	"k8s.io/minikube/pkg/minikube/config"
+	"k8s.io/minikube/pkg/minikube/driver"
 	"k8s.io/minikube/pkg/minikube/exit"
+	"k8s.io/minikube/pkg/minikube/machine"
 )
 
 // This init function is used to set the logtostderr variable to false so that INFO level log info does not clutter the CLI
@@ -44,7 +46,6 @@ func init() {
 }
 
 // Bootstrapper returns a new bootstrapper for the cluster
-// TODO(#6891): Remove node as an argument
 func Bootstrapper(api libmachine.API, bootstrapperName string, cc config.ClusterConfig, r command.Runner) (bootstrapper.Bootstrapper, error) {
 	var b bootstrapper.Bootstrapper
 	var err error
@@ -59,3 +60,21 @@ func Bootstrapper(api libmachine.API, bootstrapperName string, cc config.Cluster
 	}
 	return b, nil
 }
+
+// ControlPlaneBootstrapper returns the bootstrapper for the cluster's control plane
+func ControlPlaneBootstrapper(mAPI libmachine.API, cc *config.ClusterConfig, bootstrapperName string) (bootstrapper.Bootstrapper, error) {
+	cp, err := config.PrimaryControlPlane(cc)
+	if err != nil {
+		return nil, errors.Wrap(err, "getting primary control plane")
+	}
+	h, err := machine.LoadHost(mAPI, driver.MachineName(*cc, cp))
+	if err != nil {
+		return nil, errors.Wrap(err, "getting control plane host")
+	}
+	cpr, err := machine.CommandRunner(h)
+	if err != nil {
+		return nil, errors.Wrap(err, "getting control plane command runner")
+	}
+
+	return Bootstrapper(mAPI, bootstrapperName, *cc, cpr)
+}

pkg/minikube/config/config.go

@@ -24,6 +24,7 @@ import (
 	"os"
 
 	"github.com/pkg/errors"
+	"github.com/spf13/viper"
 
 	"k8s.io/minikube/pkg/minikube/localpath"
 )
@@ -200,3 +201,28 @@ func (c *simpleConfigLoader) WriteConfigToFile(profileName string, cc *ClusterCo
 	}
 	return ioutil.WriteFile(path, contents, 0644)
 }
+
+// MultiNodeCNIConfig add default CNI config needed for multinode clusters and saves off the config
+func MultiNodeCNIConfig(cc *ClusterConfig) error {
+	if cc.KubernetesConfig.ExtraOptions.Get("pod-network-cidr", "kubeadm") == "" {
+		cc.KubernetesConfig.NetworkPlugin = "cni"
+		if err := cc.KubernetesConfig.ExtraOptions.Set(fmt.Sprintf("kubeadm.pod-network-cidr=%s", DefaultPodCIDR)); err != nil {
+			return err
+		}
+		return SaveProfile(cc.Name, cc)
+	}
+	return nil
+}
+
+// MultiNode returns true if the cluster has multiple nodes or if the request is asking for multinode
+func MultiNode(cc ClusterConfig) bool {
+	if len(cc.Nodes) > 1 {
+		return true
+	}
+
+	if viper.GetInt("nodes") > 1 {
+		return true
+	}
+
+	return false
+}

pkg/minikube/config/profile.go

@@ -136,6 +136,13 @@ func SaveNode(cfg *ClusterConfig, node *Node) error {
 	if !update {
 		cfg.Nodes = append(cfg.Nodes, *node)
 	}
+
+	if MultiNode(*cfg) {
+		if err := MultiNodeCNIConfig(cfg); err != nil {
+			return err
+		}
+	}
+
 	return SaveProfile(viper.GetString(ProfileName), cfg)
 }
 

pkg/minikube/config/types.go

@@ -22,6 +22,14 @@ import (
 	"github.com/blang/semver"
 )
 
+const (
+	// DefaultNetwork is the Docker default bridge network named "bridge"
+	// (https://docs.docker.com/network/bridge/#use-the-default-bridge-network)
+	DefaultNetwork = "bridge"
+	// DefaultPodCIDR is The CIDR to be used for pods inside the node.
+	DefaultPodCIDR = "10.244.0.0/16"
+)
+
 // Profile represents a minikube profile
 type Profile struct {
 	Name   string

pkg/minikube/driver/driver.go

@@ -24,7 +24,6 @@ import (
 	"strings"
 
 	"github.com/golang/glog"
-	"k8s.io/minikube/pkg/drivers/kic"
 	"k8s.io/minikube/pkg/minikube/config"
 	"k8s.io/minikube/pkg/minikube/registry"
 )
@@ -163,9 +162,8 @@ func FlagDefaults(name string) FlagHints {
 	fh := FlagHints{}
 	if name != None {
 		fh.CacheImages = true
-		// only for kic, till other run-times are available we auto-set containerd.
 		if name == Docker {
-			fh.ExtraOptions = append(fh.ExtraOptions, fmt.Sprintf("kubeadm.pod-network-cidr=%s", kic.DefaultPodCIDR))
+			fh.ExtraOptions = append(fh.ExtraOptions, fmt.Sprintf("kubeadm.pod-network-cidr=%s", config.DefaultPodCIDR))
 		}
 		return fh
 	}

pkg/minikube/node/start.go

@@ -156,20 +156,7 @@ func Start(starter Starter, apiServer bool) (*kubeconfig.Settings, error) {
 		}
 
 		// Make sure to use the command runner for the control plane to generate the join token
-		cp, err := config.PrimaryControlPlane(starter.Cfg)
-		if err != nil {
-			return nil, errors.Wrap(err, "getting primary control plane")
-		}
-		h, err := machine.LoadHost(starter.MachineAPI, driver.MachineName(*starter.Cfg, cp))
-		if err != nil {
-			return nil, errors.Wrap(err, "getting control plane host")
-		}
-		cpr, err := machine.CommandRunner(h)
-		if err != nil {
-			return nil, errors.Wrap(err, "getting control plane command runner")
-		}
-
-		cpBs, err := cluster.Bootstrapper(starter.MachineAPI, viper.GetString(cmdcfg.Bootstrapper), *starter.Cfg, cpr)
+		cpBs, err := cluster.ControlPlaneBootstrapper(starter.MachineAPI, starter.Cfg, viper.GetString(cmdcfg.Bootstrapper))
 		if err != nil {
 			return nil, errors.Wrap(err, "getting control plane bootstrapper")
 		}
@@ -209,7 +196,7 @@ func Provision(cc *config.ClusterConfig, n *config.Node, apiServer bool) (comman
 	}
 
 	// Abstraction leakage alert: startHost requires the config to be saved, to satistfy pkg/provision/buildroot.
-	// Hence, saveConfig must be called before startHost, and again afterwards when we know the IP.
+	// Hence, SaveProfile must be called before startHost, and again afterwards when we know the IP.
 	if err := config.SaveProfile(viper.GetString(config.ProfileName), cc); err != nil {
 		return nil, false, nil, nil, errors.Wrap(err, "Failed to save config")
 	}