diff --git a/openldap-server/vars/main.yml b/openldap-server/vars/main.yml
new file mode 100644
index 00000000..467d84b4
--- /dev/null
+++ b/openldap-server/vars/main.yml
@@ -0,0 +1,4 @@
+---
+# IMPORTANT: openldap does not support ecdsa keys.
+letsencrypt_acme_key_type: rsa
+