Skipping of Exchange attributes during INTRA-forest synchronization (4254904)

It has been observed that during INTRA-forest synchronization all of the Exchange attributes are set to be skipped by default.

Why does this happen and what should one do if he is using some of the non-default Extension Attributes for matching purposes?

Is it still okay to have them skipped?

In the past during Intra-forest synchronization there were some issues with the Exchange attributes, therefore to be on safe side a decision was made to skip them all by default.

A simple non-technical explanation would be:

During intra-forest migration, when the checkbox "Reconnect mailboxes" is selected, the tool (DSA) would delete all Exchange attributes on source object and then it would populate the Exchange attributes on target object. This needs to be done because some of the attributes (like SMTP address) need to be unique in the org.

However, if Directory Synchronization is working it will capture the change (that the source Exchange attributes were deleted) and even if migration already populated them for the target object Directory Synchronization will still will come and remove (delete) them, synchronizing the blank attribute from source to target, so target user object could potentially lose some or all Exchange attributes. In order to stop this from occuring, all Exchange attributes are being skipped by default and should be always selected during synchronization in an Intra-forest migration.

Only the Extension Attribute 14 and 15 are not selected and are not skipped, because Extension Attribute 14 and 15 are used by default for matching purposes.

If you migration has multiple domain pairs and you need to use multiple matching attributes OR if you are using different, non-default matching attributes, then you should not skip them from synchronization, otherwise your synchronization will not work.

Eg. If you are using Extension Attribute 11 and 12 as matching attributes for QMM then you should not skip them from synchronization, you need to unselect them under synchronization properties.

 Note: modifying this setting during synchronization will require a full re-synchronization.

This article applies to Intra-forest synchronization scenarios only, if no synchronization is being used then the information in this article can be ignored.