On two OpenLDAP multi-masters on RHEL6 there is a difference of ~400k records, some modify and delete operations did not replicate

Issue

Seen in the ldap replication log:

Aug 27 03:48:02 hostname slapd[11507]: do_syncrep2: rid=003 cookie=rid=003,csn=20140827074704.978593Z#000000#000#000000
Aug 27 03:48:02 hostname slapd[11507]: do_syncrep2: rid=003 CSN too old, ignoring 20140827074704.978593Z#000000#000#000000
Aug 27 03:48:02 hostname slapd[11507]: do_syncrep2: rid=003 cookie=
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 LDAP_RES_SEARCH_ENTRY(LDAP_SYNC_DELETE)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 be_search (0)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 (null)
Aug 27 03:48:02 hostname slapd[11507]: do_syncrep2: rid=003 cookie=
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 LDAP_RES_SEARCH_ENTRY(LDAP_SYNC_DELETE)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 be_search (0)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 (null)
Aug 27 03:48:02 hostname slapd[11507]: do_syncrep2: rid=003 cookie=
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 LDAP_RES_SEARCH_ENTRY(LDAP_SYNC_DELETE)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 be_search (0)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 (null)
Aug 27 03:48:02 hostname slapd[11507]: do_syncrep2: rid=003 cookie=
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 LDAP_RES_SEARCH_ENTRY(LDAP_SYNC_DELETE)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 be_search (0)
Aug 27 03:48:02 hostname slapd[11507]: syncrepl_entry: rid=003 (null)