Check kubeletArguments["cni-bin-dir"] matches with default path used by OpenShift SDN

- If kubeletArguments["cni-bin-dir"] differs from default openshift sdn,
openshift sdn plugin will not be detected by kubelet. Pod setup fails on the node and
openshift-node service continuously spams the log.

Author: Ravi Sankar Penta

pkg/cmd/server/kubernetes/network/sdn_linux.go

@@ -1,6 +1,7 @@
 package network
 
 import (
+	"fmt"
 	"strings"
 
 	kclientv1 "k8s.io/api/core/v1"
@@ -10,6 +11,7 @@ import (
 	"k8s.io/client-go/tools/record"
 	kinternalclientset "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset"
 	kinternalinformers "k8s.io/kubernetes/pkg/client/informers/informers_generated/internalversion"
+	kcni "k8s.io/kubernetes/pkg/kubelet/network/cni"
 	"k8s.io/kubernetes/pkg/proxy/apis/kubeproxyconfig"
 
 	configapi "github.com/openshift/origin/pkg/cmd/server/apis/config"
@@ -26,6 +28,12 @@ func NewSDNInterfaces(options configapi.NodeConfig, networkClient networkclient.
 	internalNetworkInformers networkinformers.SharedInformerFactory,
 	proxyconfig *kubeproxyconfig.KubeProxyConfiguration) (network.NodeInterface, network.ProxyInterface, error) {
 
+	if cniBinPaths, ok := options.KubeletArguments["cni-bin-dir"]; ok && (len(cniBinPaths) > 0) {
+		if cniBinPaths[0] != kcni.DefaultCNIDir {
+			return nil, nil, fmt.Errorf("kubeletArguments[\"cni-bin-dir\"] did not match with default CNI binary path used by openshift SDN plugin: %q", kcni.DefaultCNIDir)
+		}
+	}
+
 	runtimeEndpoint := options.DockerConfig.DockerShimSocket
 	runtime, ok := options.KubeletArguments["container-runtime"]
 	if ok && len(runtime) == 1 && runtime[0] == "remote" {