diff --git a/roles/backup_server/templates/ferm_backup.conf.j2 b/roles/backup_server/templates/ferm_backup.conf.j2
index 360fe0013c8b77d4fd40822517b986571fe4aad2..cc055c6b1f8de46a218d0ffc31f31350c4f3df2b 100644
--- a/roles/backup_server/templates/ferm_backup.conf.j2
+++ b/roles/backup_server/templates/ferm_backup.conf.j2
@@ -1,9 +1,11 @@
 {% if backup_clients -%}
-table filter {
-    chain INPUT {
-        saddr ({% for client in backup_clients %} {{ client.ip }}{% endfor %}) @subchain "backup_in" {
-            # SSH
-            proto tcp dport 2222 ACCEPT;
+domain (ip ip6) {
+    table filter {
+        chain INPUT {
+            saddr ({% for client in backup_clients %} {{ client.ip }}{% endfor %}) @subchain "backup_in" {
+                # SSH
+                proto tcp dport 2222 ACCEPT;
+            }
         }
     }
 }