diff --git a/roles/mail_server/molecule/default/prepare.yml b/roles/mail_server/molecule/default/prepare.yml
index 78c30375132f1b072818b766c84f4fc9c337711f..e520de33671019b843863662ca8b28f9506735be 100644
--- a/roles/mail_server/molecule/default/prepare.yml
+++ b/roles/mail_server/molecule/default/prepare.yml
@@ -18,6 +18,11 @@
         update_cache: true
       changed_when: false
 
+    - name: Install tools for testing
+      apt:
+        name: gnutls-bin
+        state: present
+
 - hosts: stretch
   become: true
   tasks: