Data Sync Types

VOSS-4-UC provides the following data sync types:

Data sync type	Description
Pull from Device	Available to all device types. Pull all data from the device Pull only the schema from the device (used for LDAP) Pull data from the Change Notification Feature local data collection
Purge Local Resources	Available to all device types. Purge data from the cache
Push to Device	Available only to Cisco Unified CM devices Push data in the cache to the device
Change Notification Sync	Available only to Cisco Unified CM devices

Note

A quick import option is available to fetch only summary data that is contained in a list operation response and not the data for all instances/fields. See Data Sync Overview in the Core Guide for details.

Generally, for all sync types, VOSS-4-UC builds up the lists of entities from both VOSS-4-UC and the device, and compares them, using the key for the device entity. The key is typically the unique identifier (ID) for the record in the device we’re syncing with. For example, for Unified CM, the ID is the pkid, which is the internal Unified CM database ID.

For subscribers, a sync builds up the list of device/cucm/Users in VOSS-4-UC and then requests from the Unified CM the lists of users it currently has for the comparison. Differences in the lists are handled according to each sync type.

Related Topics

• Data Sync Overview
• Change Notification Feature Overview

Pull from Device

For sync type Pull from Device, the VOSS-4-UC resource is updated where the same key is present in both lists. In this case, the device data is the master and the VOSS-4-UC system model data is updated with the device data.

For example, let’s say new data is added to the Unified CM, so that the VOSS-4-UC system data state for a Unified CM device/cucm/User does not show instances that are shown on the Unified CM.

In this case, a pull data sync synchronizes the system data with the Unified CM data. For example, a user’s Department may be updated on the Unified CM, but the update only shows on the system after a Pull from Device sync. If a user resource is created in Unified CM but not in VOSS-4-UC, this adds the device/cucm/User instance into VOSS-4-UC at the level the pull sync was run from, for example, at the customer level.

When deleting a VOSS-4-UC resource from the device, so that the key is in the VOSS-4-UC list but not in the device list, a pull sync removes the resource in VOSS-4-UC. For example, if the resource is a user in VOSS-4-UC but not in Unified CM, the pull sync removes the device/cucm/User record in VOSS-4-UC.

To restrict the number of records removed in VOSS-4-UC, ensure you have the following named macro at the hierarchy where the sync takes place:

PULL_SYNC_DELETE_THRESHOLD_<device_type>

For details, see Pull Sync Delete Threshold.

When pulling device data, for example LDAP users from an LDAP device, the results returned to VOSS-4-UC depend on the LDAP server configuration. For example, if the returned results exceed the LDAP server configured maximum, and if the server does not support paging, an appropriate error message is returned.

Push to Device

Sync type Push to Device is available only to Cisco Unified CM device types.

In a Push to Device sync type, devices are synchronized with the VOSS-4-UC system data state, which is the primary data state.

• When deleting device data from VOSS-4-UC so that the key is in the device list but not in the VOSS-4-UC list (for example, delete user in VOSS-4-UC), the user is removed from Unified CM. The user will not exist on the device or on VOSS-4-UC.
• When adding new device data to VOSS-4-UC so that the resource shows instances that are not shown on the device, a push data sync synchronizes the device data with the VOSS-4-UC data. For example, adding a device/cucm/User instance to VOSS-4-UC and running a Push to Device sync adds the user record to Unified CM.

Keys found in both lists are ignored. Existing records are not updated in either direction.

In the device/cucm/User example, if the same user exists on both VOSS-4-UC and on Unified CM, no update occurs in either direction. Detailed settings may still not match after a Push to Device sync.

Important

When performing a push sync, it is important to consider data dependencies between different models.

For example, data dependencies may exist between users and phones in the Cisco Unified CM. In this case, if a user is associated to a phone (via the associated devices on the user), you can’t add the user if the phone does not yet exist in in Cisco Unified CM.

On the other hand, for ownerID on the phone, pushing the phone first will fail since the user isn’t in place.

This might mean running the push sync multiple times so it loads in the required order, or you may need to modify data (such as removing device association) to allow the push sync to succeed.

Note

The keys list sync logic described in this topic implies that in case of a reversion of the Unified CM to restores/inactive partitions, the end-state of the relevant pkids may differ to their state the last time VOSS-4-UC was in sync with Unified CM (before a restore), particularly if testing occurred in between. This means you may, for example, have a user with the same username in both VOSS-4-UC and Unified CM, but if that user’s pkid in Unified CM now differs to the one in VOSS-4-UC from previous syncs or interactions, they will be seen as different users even though they have the same usernames.

Change Notification Sync

Sync type Change Notification Sync is available only to Cisco Unified CM device types.

A Change Notification Sync is a pull sync of changes stored in the local collection that is updated by the Change Notification Collector service.

For more details on Change Notification Sync, see the related topics in Data Sync section of the Core Feature Guide.

Purge Local Resources

In a Purge Local Resources sync type, all resources or instances of device information that exists in the system are deleted. Entities in the device are not deleted.

Note

The default purge syncs created when adding a CUCM, CUC, LDAP or CCX server type are disabled by default. To use the purge sync, the “Remove” check box must first be cleared on the “Disabled Operations” tab of the relevant sync.

This sync type is typically used when cleaning up the system. The system displays a warning before executing an enabled purge sync.

See the following sample device type syncs:

• HcsPurge-{{CUCMHostname}}–{{CUCMClusterName}}-DS
• HcsUserPurgeDS-{{CUCMHostname}}–{{CUCMClusterName}}
• HcsPhonePurgeDS-{{CUCMHostname}}–{{CUCMClusterName}}
• HcsPurge-{{CUCXHostname}}–{{CUCXClusterName}}-DS
• PurgeUccx-{{UCCXHostName}}
• HcsLdapUserPurge–{{UniqueID}}
• PurgeSpark{{CustomerName}}