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Re: syncrepl questions

>Is the point of sending the currently present entries to do a
>comparison of that list against what is stored locally and remove
>anything that isn't the current state of the provider? If so, that
>seems like a very expensive way to handle things. Why not just keep
>deleted records around with the modification stamp indicating when they
>were deleted, and send the death notifications across which are newer
>than the last sync.

Deleted or scope-out entries are hard to detect without full history store.
For example, typical history store does not have attributes of deleted entries
nor have the previous values of modified attributes. Also, history stores
can be truncated after a fixed amount of time.
The [add+present] mode of operation is a kind of base mode that
can reliably work even when it is not possible to do incremental synchronization
with such history stores.
The LDAP Content Sync protocol also supports [add+delete] mode.
The syncrepl can be made to support the [add+delete] mode as well
when OpenLDAP supports a form of  history store.
BTW, [add+present] mode is not that expensive
with a reasonably fast hw and connection.

Jong Hyuk Choi
IBM Thomas J. Watson Research Center - Enterprise Linux Group
P. O. Box 218, Yorktown Heights, NY 10598
email: jongchoi@us.ibm.com
(phone) 914-945-3979    (fax) 914-945-4425   TL: 862-3979