Small improvements on CLI messages

cmd/kubeadm/app/cmd/phases/controlplane.go

@@ -85,17 +85,17 @@ func getControlPlaneSubCommands(outDir string) []*cobra.Command {
 		}
 
 		// Add flags to the command
-		cmd.Flags().StringVar(&cfg.CertificatesDir, "cert-dir", cfg.CertificatesDir, `The path where certificates are stored`)
-		cmd.Flags().StringVar(&cfg.KubernetesVersion, "kubernetes-version", cfg.KubernetesVersion, `Choose a specific Kubernetes version for the control plane`)
+		cmd.Flags().StringVar(&cfg.CertificatesDir, "cert-dir", cfg.CertificatesDir, `The path where certificates are stored.`)
+		cmd.Flags().StringVar(&cfg.KubernetesVersion, "kubernetes-version", cfg.KubernetesVersion, `Choose a specific Kubernetes version for the control plane.`)
 
 		if properties.use == "all" || properties.use == "apiserver" {
-			cmd.Flags().StringVar(&cfg.API.AdvertiseAddress, "apiserver-advertise-address", cfg.API.AdvertiseAddress, "The IP address the API Server will advertise it's listening on. 0.0.0.0 means the default network interface's address.")
-			cmd.Flags().Int32Var(&cfg.API.BindPort, "apiserver-bind-port", cfg.API.BindPort, "Port for the API Server to bind to")
-			cmd.Flags().StringVar(&cfg.Networking.ServiceSubnet, "service-cidr", cfg.Networking.ServiceSubnet, "Use alternative range of IP address for service VIPs")
+			cmd.Flags().StringVar(&cfg.API.AdvertiseAddress, "apiserver-advertise-address", cfg.API.AdvertiseAddress, "The IP address or DNS name the API Server is accessible on.")
+			cmd.Flags().Int32Var(&cfg.API.BindPort, "apiserver-bind-port", cfg.API.BindPort, "The port the API Server is accessible on.")
+			cmd.Flags().StringVar(&cfg.Networking.ServiceSubnet, "service-cidr", cfg.Networking.ServiceSubnet, "The range of IP address used for service VIPs.")
 		}
 
 		if properties.use == "all" || properties.use == "controller-manager" {
-			cmd.Flags().StringVar(&cfg.Networking.PodSubnet, "pod-network-cidr", cfg.Networking.PodSubnet, "Specify range of IP addresses for the pod network; if set, the control plane will automatically allocate CIDRs for every node")
+			cmd.Flags().StringVar(&cfg.Networking.PodSubnet, "pod-network-cidr", cfg.Networking.PodSubnet, "The range of IP addresses used for the pod network.")
 		}
 
 		cmd.Flags().StringVar(&cfgPath, "config", cfgPath, "Path to kubeadm config file (WARNING: Usage of a configuration file is experimental)")

cmd/kubeadm/app/cmd/phases/kubeconfig.go

@@ -112,15 +112,15 @@ func getKubeConfigSubCommands(out io.Writer, outDir string) []*cobra.Command {
 		if properties.use != "user" {
 			cmd.Flags().StringVar(&cfgPath, "config", cfgPath, "Path to kubeadm config file (WARNING: Usage of a configuration file is experimental)")
 		}
-		cmd.Flags().StringVar(&cfg.CertificatesDir, "cert-dir", cfg.CertificatesDir, "The path where to save and store the certificates")
-		cmd.Flags().StringVar(&cfg.API.AdvertiseAddress, "apiserver-advertise-address", cfg.API.AdvertiseAddress, "The IP address the API Server will advertise it's listening on. 0.0.0.0 means the default network interface's address.")
-		cmd.Flags().Int32Var(&cfg.API.BindPort, "apiserver-bind-port", cfg.API.BindPort, "Port for the API Server to bind to")
+		cmd.Flags().StringVar(&cfg.CertificatesDir, "cert-dir", cfg.CertificatesDir, "The path where certificates are stored.")
+		cmd.Flags().StringVar(&cfg.API.AdvertiseAddress, "apiserver-advertise-address", cfg.API.AdvertiseAddress, "The IP address or DNS name the API Server is accessible on.")
+		cmd.Flags().Int32Var(&cfg.API.BindPort, "apiserver-bind-port", cfg.API.BindPort, "The port the API Server is accessible on.")
 		if properties.use == "all" || properties.use == "kubelet" {
-			cmd.Flags().StringVar(&cfg.NodeName, "node-name", cfg.NodeName, `Specify the node name`)
+			cmd.Flags().StringVar(&cfg.NodeName, "node-name", cfg.NodeName, `The node name that the kubelet client cert should use.`)
 		}
 		if properties.use == "user" {
-			cmd.Flags().StringVar(&token, "token", token, "The path to the directory where the certificates are.")
-			cmd.Flags().StringVar(&clientName, "client-name", clientName, "The name of the client for which the KubeConfig file will be generated.")
+			cmd.Flags().StringVar(&token, "token", token, "The token that should be used as the authentication mechanism for this kubeconfig.")
+			cmd.Flags().StringVar(&clientName, "client-name", clientName, "The name of the KubeConfig user that will be created. Will also be used as the CN if client certs are created.")
 		}
 
 		subCmds = append(subCmds, cmd)

cmd/kubeadm/app/cmd/phases/markmaster.go

@@ -31,7 +31,7 @@ func NewCmdMarkMaster() *cobra.Command {
 	var kubeConfigFile string
 	cmd := &cobra.Command{
 		Use:     "mark-master <node-name>",
-		Short:   "Create KubeConfig files from given credentials.",
+		Short:   "Mark a node as master.",
 		Aliases: []string{"markmaster"},
 		RunE: func(_ *cobra.Command, args []string) error {
 			err := validateExactArgNumber(args, []string{"node-name"})