diff --git a/rootfs/etc/confd/templates/10-auth.conf.tmpl b/rootfs/etc/confd/templates/10-auth.conf.tmpl
index 4409fdc..5b59c14 100644
--- a/rootfs/etc/confd/templates/10-auth.conf.tmpl
+++ b/rootfs/etc/confd/templates/10-auth.conf.tmpl
@@ -1,3 +1,3 @@
-auth_username_chars = {{getenv "ALLOWEDUSERNAMECHARS"}}
-auth_mechanisms = {{getenv "AUTHMECHANISMS"}}
+auth_username_chars = {{getenv "ALLOWED_USERNAME_CHARS" "äöüabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@"}}
+auth_mechanisms = {{getenv "AUTH_MECHANISMS" "plain login"}}
 !include auth-ldap.conf.ext