.. _data_sync:

Data Sync Overview and Key Settings
-----------------------------------

The data of the various devices can be updated on |VOSS-4-UC|, or also directly on
the device. Therefore, it is necessary to periodically synchronize cached
|VOSS-4-UC| data with the data on devices.  

Consider an example: when an instance of a |Unified CM| is added to the system,
its data is imported and cached. However, when instances are added, updated or removed
from the |Unified CM|, the cached data in |VOSS-4-UC| becomes out of sync with
data on the device.

If data is deleted from |Unified CM| before it is deleted from
|VOSS-4-UC|, the error "The specified resource could not be found" is
displayed. This means the resource is out of sync and |VOSS-4-UC| may need 
to re-sync with |Unified CM| to delete or update it.

The Data Sync feature provides a means to dynamically synchronize 
cached |VOSS-4-UC| data with data on devices. The data sync instance
is associated with the connection parameters of a device type
in |VOSS-4-UC|.

Supported devices include:

* HCM-F (if installed) 
* Cisco Unified CM
* Cisco Unity Connection
* LDAP
* WebEx

Individual Add, Update and Delete operations carried out by a data sync
instance can be disabled on the user interface. If no operation is selected,
the default behavior is maintained.

Refer to the Best Practices Guide chapter on Data Sync for additional considerations
when managing your data syncs.


.. |VOSS-4-UC| replace:: VOSS-4-UC
.. |Unified CM| replace:: Unified CM