Replication problem with slurpd

[Raphaël Ouazana-Sustowski <raphael.ouazana@linagora.com>]

I have a problem with slurpd. I have one master which replicates on 2
slaves which one replicates on one other slave.
M -> S1
  -> S/M -> S2
They are all OpenLDAP 2.2.11 (I tested once with 2.2.16 and had the same
problem).

Each night I delete all the entries of the 4 directories and re-populate
the master (M) with ldapadd. So slurpd of the Master populates S1 and
the Slave/Master (S/M) ; and slurpd of S/M populates S2.
The problem is that when I check if all entries are really in the 4
directories, I can see that some are missing (about 0 to 4, rarely
more)! For example I can have :
M : 118821 entries
S1 : 118819
M/S : 118819
S2 : 118818
Of course I have nothing in .rej files, and see nothing in slurpd logs
when I activate them.

Moreother the problem seems to be pretty hard to reproduce. I tried to
reproduce it with test data but don't success. So I'm looking for
methods to analyse the problem. For example how to log properly slurpd ?

Raphael Ouazana.