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Re: contextCSN values and MMR
On Sat, 10 Aug 2013, Michael StrÃder wrote:
Are contextCSN values on all replicas really in sync if changes were correctly
I've implemented a monitoring check used with normal MMR setup (OpenLDAP
2.4.35, own build on Debian Squeeze) which also checks the contextCSN values
on all replicas compared by server-id.
Sometimes we observe, even in isolated tests, that contextCSN values for a
certain server-id differ for quite a while (up to hours) even though the
changes coming from that server were definitely replicated to all other
replicas. After a while the contextCSN values get suddenly updated.
Unfortunately this does not always happen.
Any hint is highly appreciated.
I have always suspected that this is due to the specific setting of:
syncprov-checkpoint <ops> <minutes>
After a write operation has succeeded, write the contextCSN to the underlying database if <ops> write
operations or more than <minutes> time have passed since the last checkpoint. Checkpointing is disabled
Not sure though.
Christian Kratzer CK Software GmbH
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