diff --git a/servers/slapd/back-ldbm/index.c b/servers/slapd/back-ldbm/index.c
index fd13d7ec07..100b058b73 100644
--- a/servers/slapd/back-ldbm/index.c
+++ b/servers/slapd/back-ldbm/index.c
@@ -3,6 +3,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <sys/types.h>
+#include <sys/socket.h>
 #include "slap.h"
 #include "back-ldbm.h"