diff --git a/util/time/duration.go b/util/time/duration.go
index 36ba97a1..49550e5e 100644
--- a/util/time/duration.go
+++ b/util/time/duration.go
@@ -6,6 +6,8 @@ import (
 	"fmt"
 	"strconv"
 	"time"
+
+	"gopkg.in/yaml.v3"
 )
 
 type Duration int64
@@ -53,6 +55,31 @@ loop:
 	return time.ParseDuration(fmt.Sprintf("%dh%s", hours, s[p:]))
 }
 
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return time.Duration(d).String(), nil
+}
+
+func (d *Duration) UnmarshalYAML(n *yaml.Node) error {
+	var v interface{}
+	if err := yaml.Unmarshal([]byte(n.Value), &v); err != nil {
+		return err
+	}
+	switch value := v.(type) {
+	case float64:
+		*d = Duration(time.Duration(value))
+		return nil
+	case string:
+		dv, err := ParseDuration(value)
+		if err != nil {
+			return err
+		}
+		*d = Duration(dv)
+		return nil
+	default:
+		return fmt.Errorf("invalid duration")
+	}
+}
+
 func (d Duration) MarshalJSON() ([]byte, error) {
 	return json.Marshal(time.Duration(d).String())
 }
diff --git a/util/time/duration_test.go b/util/time/duration_test.go
index 12447510..0324e68a 100644
--- a/util/time/duration_test.go
+++ b/util/time/duration_test.go
@@ -5,8 +5,44 @@ import (
 	"encoding/json"
 	"testing"
 	"time"
+
+	"gopkg.in/yaml.v3"
 )
 
+func TestMarshalYAML(t *testing.T) {
+	d := Duration(10000000)
+	buf, err := yaml.Marshal(d)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(buf, []byte(`10ms
+`)) {
+		t.Fatalf("invalid duration: %s != %s", buf, `10ms`)
+	}
+}
+
+func TestUnmarshalYAML(t *testing.T) {
+	type str struct {
+		TTL Duration `yaml:"ttl"`
+	}
+	v := &str{}
+	var err error
+
+	err = yaml.Unmarshal([]byte(`{"ttl":"10ms"}`), v)
+	if err != nil {
+		t.Fatal(err)
+	} else if v.TTL != 10000000 {
+		t.Fatalf("invalid duration %v != 10000000", v.TTL)
+	}
+
+	err = yaml.Unmarshal([]byte(`{"ttl":"1y"}`), v)
+	if err != nil {
+		t.Fatal(err)
+	} else if v.TTL != 31622400000000000 {
+		t.Fatalf("invalid duration %v != 31622400000000000", v.TTL)
+	}
+}
+
 func TestMarshalJSON(t *testing.T) {
 	d := Duration(10000000)
 	buf, err := json.Marshal(d)