Updating the offline address book
To move OAB generation to another server, you need to move the organization mailbox.For example: Remember, you can configure multiple OABs to use the same organization mailbox, but you can't configure an OAB to use more than one organization mailbox.The default setting restricts OAB distribution to the OAB virtual directories on the server that holds the OAB's organization mailbox.However, the Client Access services on Mailbox server can proxy incoming OAB download requests to the correct location.
Autodiscover is supported by all versions of Outlook and virtually all mobile devices that are currently by Exchange.
Here's a summary of the OAB distribution process: If a shadow copy of the OAB exists in an organization mailbox in the local Active Directory site (the site where the user is connecting from), then a local Mailbox server is used to download the OAB.
However, synchronization of the shadow copy between organization mailboxes is performed on-demand.
This OAB is also the default OAB, which means it's the OAB that's used by mailboxes and mailbox databases that don't have an OAB assigned to them.
OABs in Exchange 2016 are improved over OABs in Exchange 2010.