diff --git a/machines/migrations/0077_auto_20180409_2243.py b/machines/migrations/0077_auto_20180409_2243.py
new file mode 100644
index 00000000..3ac63072
--- /dev/null
+++ b/machines/migrations/0077_auto_20180409_2243.py
@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-04-09 20:43
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('machines', '0076_auto_20180130_1623'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='extension',
+            name='origin',
+            field=models.ForeignKey(blank=True, help_text='Enregistrement A associé à la zone', null=True, on_delete=django.db.models.deletion.PROTECT, to='machines.IpList'),
+        ),
+    ]
diff --git a/machines/models.py b/machines/models.py
index dc2dba65..5af11b36 100644
--- a/machines/models.py
+++ b/machines/models.py
@@ -484,7 +484,7 @@ class Extension(RevMixin, AclMixin, models.Model):
         help_text="Nom de la zone, doit commencer par un point (.example.org)"
     )
     need_infra = models.BooleanField(default=False)
-    origin = models.OneToOneField(
+    origin = models.ForeignKey(
         'IpList',
         on_delete=models.PROTECT,
         blank=True,
diff --git a/machines/serializers.py b/machines/serializers.py
index f1888750..42ca679d 100644
--- a/machines/serializers.py
+++ b/machines/serializers.py
@@ -175,7 +175,7 @@ class ExtensionSerializer(serializers.ModelSerializer):
         fields = ('name', 'origin', 'origin_v6', 'zone_entry', 'soa')
 
     def get_origin_ip(self, obj):
-        return obj.origin.ipv4
+        return getattr(obj.origin, 'ipv4', None)
 
     def get_zone_name(self, obj):
         return str(obj.dns_entry)