Thanks for the follow up Quanah,

Version: OpenLDAP: slapd 2.4.56
We use delta sync replication
We have been provisioning 2 new providers to achieve multi master for a total 
of 3 providers. We have been testing the newly provisioned databases for 
accuracy with the ldiff-diff tool provided by 
https://github.com/pingidentity/ldapsdk

Provision Process:
1. Take backup of database with mdb_copy on initial provider.
2. Load database schema / config on new provider.
3. replace default DB with backup DB on new provider
4. Add access log overlay / access log database to DB on new provider
5. Turn on delta sync replication for new provider so it "catches up" from the 
original provider.

We historically did not have olcSpCheckpoint set to a value so we theorize the 
backup databases were newer in state than indicated by the contextCSN in the 
backed up database. Through testing specifically around deleting a user group 
containing hundreds of users between when the backup was taken and the new 
provider enabled w/ replication (so the new provider had to catch up with the 
user group delete) we noticed incorrect final state on the newly provisioned 
provider. Not until we added CSN checkpointing did the restores start to be 
100% accurate. Given our theory that the newly provisioned database is syncing 
from the last checkpointed CSN and forming inconsistencies we wanted to set 
olcSpCheckpoint: 1 1, to never have a discrepancy between database state and 
the CSN in the backed up database.

Initial testing shows `olcSpCheckpoint: 1 1` to function fine, but we wanted to 
be cautious about setting to this frequency in case there were any known issues 
doing such a frequent setting.

Thanks,
Tom

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