Key Settings for Data Sync
--------------------------

.. _18.1.2|DOC-225:


A number of key settings that are available for data sync:

* Model Type lists - define which entities to pull in a given sync (for example, only
  pull in ``device/cucm/User`` records from Cisco Unified CM).
* Model Instance filters - limit a sync to a subset of entities in a sync (for example,
  pull in users with a primary extension starting with 1). This setting requires a system
  level administrator to expose it on the GUI.
* Actions - select which actions (Add/Update/Delete) are active for a sync.  Update tends
  to be the most effort to run, because for most systems this involves a GET API call for
  each record and comparing to our data.  Add/Del can be determined from the initial list
  API calls.  If you are really only need the Add and/or Del action, then disabling the
  Update action will likely save considerable time on the sync.
* Quick Import - use the list API responses to update the VOSS-4-UC cache
  and will not do individual GET calls for each entity for the update.  This works well
  where the list response contains all the values for the entity or only key settings need
  to be updated.  The removal of all the individual GETs means the sync occurs much faster,
  because VOSS-4-UC is not waiting for the API responses when there are a many entities to
  update.  This is useful if the list and GET responses are needed or if you only need the
  summary data from the list view.

.. note::
   The Quick Import option is not recommended in most cases, but should only be
   used for the sync of  ``device/cuc/ImportUser``. However, *initially* there
   is an exception to the performance improvement of a quick import sync with
   ``device/cuc/User``:
   
   When quick import is turned on on a sync which has previously run without it, dependent, 
   non-Import User model types use the LIST response data to compare with the resource data
   which was originally saved using the GET response data.  The data sync detects a change
   and a resource save is initiated for each instance. In the case of ``device/cuc/User``, this
   means that dependent import API calls are made,  which result in a long sync time.
    
   Once it has completed, however, *subsequent* quick import syncs should show an improvement
   over non-quick import syncs, but when changing back to a non-quick import sync, the same
   effect would likely be observed.
   

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