diff --git a/internal/definitions/common/time.go b/internal/definitions/common/time.go
new file mode 100644
index 0000000..0a365e6
--- /dev/null
+++ b/internal/definitions/common/time.go
@@ -0,0 +1,34 @@
+package common
+
+import (
+	"encoding/json"
+	"errors"
+	"time"
+)
+
+type Duration struct {
+	time.Duration
+}
+
+// MarshalJSON for IPNet
+func (i Duration) MarshalJSON() ([]byte, error) {
+	return json.Marshal(int(i.Seconds()))
+}
+
+// UnmarshalJSON for IPNet
+func (i *Duration) UnmarshalJSON(b []byte) error {
+	var v interface{}
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+	switch value := v.(type) {
+	case float64:
+		i.Duration = time.Second * time.Duration(value)
+		return nil
+	case int:
+		i.Duration = time.Second * time.Duration(value)
+		return nil
+	default:
+		return errors.New("invalid duration")
+	}
+}
diff --git a/internal/definitions/service/dhcp_v4_server.go b/internal/definitions/service/dhcp_v4_server.go
index 987fb77..35ccd52 100644
--- a/internal/definitions/service/dhcp_v4_server.go
+++ b/internal/definitions/service/dhcp_v4_server.go
@@ -1,14 +1,12 @@
 package service
 
-import (
-	"time"
-)
+import "nfsense.net/nfsense/internal/definitions/common"
 
 type DHCPv4Server struct {
-	Interface        string        `json:"interface"`
-	Pool             []string      `json:"pool"`
-	DefaultLeaseTime time.Duration `json:"default_lease_time"`
-	MaxLeaseTime     time.Duration `json:"max_lease_time"`
+	Interface        string          `json:"interface"`
+	Pool             []string        `json:"pool"`
+	DefaultLeaseTime common.Duration `json:"default_lease_time"`
+	MaxLeaseTime     common.Duration `json:"max_lease_time"`
 
 	GatewayMode   Mode      `json:"gateway_mode"`
 	Gateway       *string   `json:"gateway,omitempty"`
diff --git a/internal/dhcp_server/template.go b/internal/dhcp_server/template.go
index efaa6f3..ac0b671 100644
--- a/internal/dhcp_server/template.go
+++ b/internal/dhcp_server/template.go
@@ -8,8 +8,8 @@ import (
 	"strconv"
 	"strings"
 	"text/template"
-	"time"
 
+	"nfsense.net/nfsense/internal/definitions/common"
 	"nfsense.net/nfsense/internal/definitions/config"
 	"nfsense.net/nfsense/internal/util"
 )
@@ -66,7 +66,7 @@ func getAddressObjectAsPoolRange(conf config.Config, name string) string {
 	return strings.ReplaceAll(conf.Object.Addresses[name].Range.String(), "-", " ")
 }
 
-func getTimeInSecond(dur time.Duration) string {
+func getTimeInSecond(dur common.Duration) string {
 	return fmt.Sprintf("%d", int(dur.Seconds()))
 }