ppolicy overlay and MMR experiencing frequent delta-sync lost issue

[Beth Halsema <bhalsema@purdue.edu>]

We are running Openldap 2.4.44 on RHEL6 in a delta-syncrepl MMR
configuration.  We are using the ppolicy overlay.  This setup is 
resulting in frequent occurrences on the consumers of:

* delta-sync lost
* traversal of the entire directory
* delta-syncrepl switches back into refreshAndPersist
* slapd memory usage increasing

We have found that this behavior is consistently triggered when the
operation that is being replicated involves a password change in
combination with the removal of ppolicy attributes (e.g. pwdGraceUseTime
and pwdFailureTime).

The detailed debugging output associated with such an occurrence is:
------------------------------------------------------------------------------
58739e68 bdb_modify_internal: replace userPassword
58739e68 bdb_modify_internal: replace pwdChangedTime
58739e68 bdb_modify_internal: softdel pwdGraceUseTime
58739e68 bdb_modify_internal: add pwdHistory
58739e68 bdb_modify_internal: replace entryCSN
58739e68 bdb_modify_internal: replace modifiersName
58739e68 bdb_modify_internal: replace modifyTimestamp
58739e68 bdb_modify_internal: delete pwdGraceUseTime
58739e68 bdb_modify_internal: 16 modify/delete: pwdGraceUseTime: no such attribute
...
58739e68 do_syncrep2: rid=001 delta-sync lost sync on (reqStart=20170109142959.000006Z,cn=log), switching to REFRESH
------------------------------------------------------------------------------

We have submitted OpenLDAP-ITS #8561 with a unit test and a possible patch to
the ppolicy overlay.

If anyone else has run into this, we would be interested in any other work-
arounds that have been used to address the issue.

Thank you!
Beth

-------------------------------------------------------------------------
Beth A. Halsema - GSEC, GSSP-Java          email:bhalsema@purdue.edu
Sofware Engineer, Identity & Access Management
OVPIT - IT Security and Policy
3495 Kent Avenue, Suite 100                Fax  :  (765) 464-2233
West Lafayette, IN  47906                  Campus Mail:  ROSS