Skip communicating with kubernetes api failures

Multus is failing when can't communicate with kube-api, which fails
to create pods even in case of not using network attachment.

This change makes multus skip the failures of communicating with kube-api
and create the networks of delegates

Signed-off-by: Mamduh Alassi <mamduhala@mellanox.com>

pkg/multus/multus.go

@@ -549,8 +549,10 @@ func CmdAdd(args *skel.CmdArgs, exec invoke.Exec, kubeClient *k8s.ClientInfo) (c
 					return nil, cmdErr(k8sArgs, "error getting pod by service unavailable: %v", err)
 				}
 			} else {
-				// Other case, return error
-				return nil, cmdErr(k8sArgs, "error getting pod: %v", err)
+				// Other case, print warning and return nil
+				logging.Debugf("%v", cmdErr(k8sArgs, "error getting pod: %v", err))
+				kubeClient = nil
+				err = nil
 			}
 		}
 	}
@@ -670,7 +672,7 @@ func CmdAdd(args *skel.CmdArgs, exec invoke.Exec, kubeClient *k8s.ClientInfo) (c
 	}
 
 	// set the network status annotation in apiserver, only in case Multus as kubeconfig
-	if n.Kubeconfig != "" && kc != nil {
+	if n.Kubeconfig != "" && kc != nil && kubeClient != nil {
 		if !types.CheckSystemNamespaces(string(k8sArgs.K8S_POD_NAME), n.SystemNamespaces) {
 			err = k8s.SetNetworkStatus(kubeClient, k8sArgs, netStatus, n)
 			if err != nil {
@@ -777,8 +779,10 @@ func CmdDel(args *skel.CmdArgs, exec invoke.Exec, kubeClient *k8s.ClientInfo) er
 				// If not found, proceed to remove interface with cache
 				pod = nil
 			} else {
-				// Other case, return error
-				return cmdErr(k8sArgs, "error getting pod: %v", err)
+				// Other case, print warning and return nil
+				logging.Debugf("%v", cmdErr(k8sArgs, "error getting pod: %v", err))
+				kubeClient = nil
+				err = nil
 			}
 		}
 	}
@@ -837,7 +841,7 @@ func CmdDel(args *skel.CmdArgs, exec invoke.Exec, kubeClient *k8s.ClientInfo) er
 	}
 
 	// unset the network status annotation in apiserver, only in case Multus as kubeconfig
-	if in.Kubeconfig != "" {
+	if in.Kubeconfig != "" && kubeClient != nil {
 		if netnsfound {
 			if !types.CheckSystemNamespaces(string(k8sArgs.K8S_POD_NAMESPACE), in.SystemNamespaces) {
 				err := k8s.SetNetworkStatus(kubeClient, k8sArgs, nil, in)