diff --git a/topologie/migrations/0041_transferportsw.py b/topologie/migrations/0041_transferportsw.py
index a629c7e6..9e1d979a 100644
--- a/topologie/migrations/0041_transferportsw.py
+++ b/topologie/migrations/0041_transferportsw.py
@@ -12,6 +12,10 @@ class Migration(migrations.Migration):
     ]
 
     operations = [
+    migrations.AlterUniqueTogether(
+        name='port',
+        unique_together=set([]),
+    ),
     migrations.RemoveField(
         model_name='port',
         name='switch',
diff --git a/topologie/migrations/0045_auto_20180326_0123.py b/topologie/migrations/0045_auto_20180326_0123.py
new file mode 100644
index 00000000..cf621967
--- /dev/null
+++ b/topologie/migrations/0045_auto_20180326_0123.py
@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-03-25 23:23
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('topologie', '0044_auto_20180326_0002'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='port',
+            name='switch',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='ports', to='topologie.Switch'),
+        ),
+    ]
diff --git a/topologie/migrations/0046_auto_20180326_0129.py b/topologie/migrations/0046_auto_20180326_0129.py
new file mode 100644
index 00000000..dc5e849e
--- /dev/null
+++ b/topologie/migrations/0046_auto_20180326_0129.py
@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-03-25 23:29
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('topologie', '0045_auto_20180326_0123'),
+    ]
+
+    operations = [
+        migrations.AlterUniqueTogether(
+            name='port',
+            unique_together=set([('switch', 'port')]),
+        ),
+    ]