diff --git a/config/validate/rules.go b/config/validate/rules.go
index 87f2d08..7651819 100644
--- a/config/validate/rules.go
+++ b/config/validate/rules.go
@@ -76,7 +76,7 @@ func checkValidity(cfg node, report *Report) {
 
 func checkNodeValidity(n, g node, r *Report) {
 	if err := config.AssertValid(n.Value, g.field.Tag.Get("valid")); err != nil {
-		r.Warning(n.line, fmt.Sprintf("invalid value %v", n.Value))
+		r.Error(n.line, fmt.Sprintf("invalid value %v", n.Value))
 	}
 	switch g.Kind() {
 	case reflect.Struct:
diff --git a/config/validate/rules_test.go b/config/validate/rules_test.go
index e3ec1f6..ab6d157 100644
--- a/config/validate/rules_test.go
+++ b/config/validate/rules_test.go
@@ -218,7 +218,7 @@ func TestCheckValidity(t *testing.T) {
 		},
 		{
 			config:  "coreos:\n  units:\n    - command: lol",
-			entries: []Entry{{entryWarning, "invalid value lol", 3}},
+			entries: []Entry{{entryError, "invalid value lol", 3}},
 		},
 
 		// struct
@@ -227,7 +227,7 @@ func TestCheckValidity(t *testing.T) {
 		},
 		{
 			config:  "coreos:\n  update:\n    reboot_strategy: always",
-			entries: []Entry{{entryWarning, "invalid value always", 3}},
+			entries: []Entry{{entryError, "invalid value always", 3}},
 		},
 
 		// unknown