ITS#5430 syncprov/glue can be used two different ways

diff --git a/servers/slapd/syncrepl.c b/servers/slapd/syncrepl.c
index d575e245bc4e7c0952ae5ce9782e89d1eb546c82..e8ddee979ae93582507bc97db7dc683f324cee4b 100644 (file)
--- a/servers/slapd/syncrepl.c
+++ b/servers/slapd/syncrepl.c
@@ -1203,9 +1203,21 @@ do_syncrepl(
        op->o_managedsait = SLAP_CONTROL_NONCRITICAL;
        be = si->si_be;
 
-       /* If we're glued, send writes through the glue parent */
+       /* Coordinate contextCSN updates with any syncprov overlays
+        * in use. This may be complicated by the use of the glue
+        * overlay.
+        *
+        * Typically there is a single syncprov mastering the entire
+        * glued tree. In that case, our contextCSN updates should
+        * go to the master DB.
+        *
+        * Alternatively, there may be individual syncprov overlays
+        * on each glued branch. In that case, each syncprov only
+        * knows about changes within its own branch. And so our
+        * contextCSN updates should only go to the local DB.
+        */
        if ( !si->si_wbe ) {
-               if ( SLAP_GLUE_SUBORDINATE( be )) {
+               if ( SLAP_GLUE_SUBORDINATE( be ) && !overlay_is_inst( be, "syncprov" )) {
                        si->si_wbe = select_backend( &be->be_nsuffix[0], 1 );
                } else {
                        si->si_wbe = be;