diff --git a/docs/rolereference.rst b/docs/rolereference.rst
index d21654ce69aceb50764000c4fc5f024619ef10bd..084e3702c648edb0dc68c4c85debd8487df4b639 100644
--- a/docs/rolereference.rst
+++ b/docs/rolereference.rst
@@ -1309,7 +1309,7 @@ Parameters
 **smtp_relay_host_port** (integer, optional, ``None``)
   Port to use when connecting to the SMTP relay host.
 
-**smtp_relay_truststore** (string, optional, ``{{ lookup('file', tls_certificate_dir + '/truststore.pem') }}``)
+**smtp_relay_truststore** (string, mandatory)
   X.509 certificate chain used for issuing certificate for the SMTP relay
   service. The file will be stored in location
   ``/etc/ssl/certs/smtp_relay_truststore.pem``