diff --git a/cmd/root.go b/cmd/root.go
index d50dd05b4..caea25992 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -22,6 +22,7 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 	"github.com/spf13/viper"
+	"reflect"
 )
 
 var (
@@ -109,6 +110,11 @@ func setAllConfig(v *viper.Viper, flags *pflag.FlagSet, envPrefix string) error
 	v.AutomaticEnv()
 
 	c := v.GetString("config")
+	var flagErr error
+	validTags := make(map[string]bool)
+	flags.VisitAll(func(f *pflag.Flag) {
+		validTags[f.Name] = true
+	})
 
 	// add config file to viper
 	if c != "" {
@@ -118,10 +124,16 @@ func setAllConfig(v *viper.Viper, flags *pflag.FlagSet, envPrefix string) error
 		if err != nil {
 			return fmt.Errorf("error reading configuration file '%s': %v", c, err)
 		}
+
+		for _, key := range v.AllKeys() {
+			if _, ok := validTags[key]; !ok {
+				return fmt.Errorf("invalid tag: %v", key)
+			}
+		}
+
 	}
 
 	// set all values from viper
-	var flagErr error
 	flags.VisitAll(func(f *pflag.Flag) {
 		if flagErr != nil {
 			return
@@ -151,3 +163,27 @@ func setAllConfig(v *viper.Viper, flags *pflag.FlagSet, envPrefix string) error
 	})
 	return flagErr
 }
+
+func GetValidTags(v interface{}) map[string]bool {
+	validTag := make(map[string]bool)
+	conf := reflect.ValueOf(v)
+
+	for i := 0; i < conf.Type().NumField(); i++ {
+		field := conf.Field(i)
+		if field.Kind() == reflect.Struct {
+			tag := conf.Type().Field(i).Tag.Get("toml")
+			tagString := strings.Split(tag, ",")
+			val := reflect.ValueOf(field.Interface())
+			for j := 0; j < val.Type().NumField(); j++ {
+				subTag := val.Type().Field(j).Tag.Get("toml")
+				subTagString := strings.Split(subTag, ",")
+				validTag[fmt.Sprintf("%s.%s", tagString[0], subTagString[0])] = true
+			}
+		} else {
+			tomlTag := conf.Type().Field(i).Tag.Get("toml")
+			s := strings.Split(tomlTag, ",")
+			validTag[s[0]] = true
+		}
+	}
+	return validTag
+}
diff --git a/cmd/root_test.go b/cmd/root_test.go
index 16bc82a8a..d3aeeab1f 100644
--- a/cmd/root_test.go
+++ b/cmd/root_test.go
@@ -171,3 +171,27 @@ func TestRootCommand(t *testing.T) {
 		t.Fatalf("Expected standard usage message from RootCommand, but err: '%v', output: '%s'", err, outStr)
 	}
 }
+
+func TestRootCommand_Config(t *testing.T) {
+	file, err := ioutil.TempFile("", "test.conf")
+	if err != nil {
+		panic(err)
+	}
+	config := `data-dir = "/tmp/pil5_0"
+bind = "127.0.0.1:15000"
+
+[cluster]
+  poll-interval = "2m0s"
+  replicas = 2
+  partitions = 128
+  hosts = [
+    "127.0.0.1:15000",
+    "127.0.0.1:15001",
+  ]`
+	file.Write([]byte(config))
+	file.Close()
+	_, err = ExecNewRootCommand(t, "server", "--config", file.Name())
+	if err.Error() != "invalid tag: cluster.partitions" {
+		t.Fatalf("Expected invalid tag, but err: '%v'", err)
+	}
+}