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Re: Sync replication failure during startup.

Stelios Grigoriadis wrote:
OpenLDAP v. 2.3.32
Berkeley DB 4.6
gcc 4.1.0

Replication doesn't work if the master server is started after the replica servers and a large amount of simoultaneous updates are performed while the server is starting up.

The entries that didn't get replicated to the replicas will not
be replicated even after a restart of both master and replicas.
The contextCSN is set to a value larger than the entryCSN of the
"lost" entries.

This is what I think happens during a master server startup with
simoultaneous updates ongoing (and replicas trying to sync in the
initial phase).

Suppose that two clients (Client1 and Client2) are adding the entries
a and b respectively. If that happens between t1 and t2 (one second
they will get the same entryCSN (same timestamp).

No, entryCSNs include both a counter and a timestamp; multiple updates within the same time quantum will still have unique CSNs.

However, some bugs related to syncprov were fixed in 2.3.34 that may be relevant here. You should upgrade to the current stable release, 2.3.38 and see if the issue remains.

  -- Howard Chu
  Chief Architect, Symas Corp.  http://www.symas.com
  Director, Highland Sun        http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP     http://www.openldap.org/project/