diff --git a/doc/guide/admin/overlays.sdf b/doc/guide/admin/overlays.sdf
index 6df98ee2d1..7e37e0ca7b 100644
--- a/doc/guide/admin/overlays.sdf
+++ b/doc/guide/admin/overlays.sdf
@@ -108,7 +108,7 @@ The following is an example used for {{SECT:delta-syncrepl replication}}:
 >        directory /usr/local/var/openldap-accesslog
 >        rootdn cn=accesslog
 >        index default eq
->        index entryCSN,objectClass,reqEnd,reqResult,reqStart
+>        index entryCSN,objectClass,reqEnd,reqResult,reqStart,reqDN
 
 Accesslog overlay definitions for the primary db