Failed to connect to the back-end database. Lync Server The CDR service will continuously attempt to reconnect to the back-end. ...

Failed to connect to the back-end database.  Lync Server The CDR service will continuously attempt to reconnect to the back-end.  Until it reconnects, incoming messages will remain in the queue.

Database connection string : %1
Cause: Possible issues with back-end database.
Resolution:
Ensure the CDR back-end database is functioning correctly.