# SDS - General Guidelines and Limitations

The SDS feature allows data-sharing between MiVoice Business systems. The following limitations apply:

- SDS does not support the merging of independent data-sharing communities. If two SDS communities have been created independent of each other, the system rejects all attempts to start sharing from one community to the other. If you wish to start sharing between communities, you must disassemble one of the communities (preferably, the community with fewer elements) and then add the individual elements to the existing larger community. See Removing an Element for more information on removing elements from a community. See Start Sharing with a New Element for instructions on how to add the elements into the existing larger community.

- All data-sharing elements must share in at the network-level scope:

- Elements must share at network-level scope before they can share at the Network Group scope or Administrative Group scope.

- Elements must share at the network-level scope before they can share at the cluster-level. This data-sharing hierarchy is maintained and enforced by the SDS feature.

- To support administrative groups in an SDS network, you must upgrade all the elements in the data sharing network to MCD Release 4.0 or later. After you upgrade the network elements, they are automatically added to the "System Default" administrative group. If there are elements with pre-MCD Release 4.0 software that are sharing data in the network, you will not be able to apply the Admin Group Members scope to form data.

- When implementing a new SDS network, enable data-sharing for a limited number of forms in order to prevent data from being overwritten in error. Once the SDS network is operational, enable data-sharing for other forms.

- In MCD Release 4.0, you cannot create and manage network groups. All elements in the network belong to one Network Group.

- There is a maximum number of elements that you can have in a data sharing community. Refer to the MiVoice Business Engineering Guidelines for specifics.

- SDS does not allow data-sharing between network elements that are separated by a firewall.

- SDS does not support Network Address Translation (NAT).

- Depending on the number of elements selected, the sizes of the databases, and the number of database mismatches, a System Data Synchronization operation can take from several minutes to several hours. Only perform synchronizations during periods of low network traffic (after normal business hours).

- When you modify data through the System Administration, Group Administration Tool, or Desktop Tool, it is distributed by SDS across the network and it can take several seconds depending on the system and network load before the modification is made on the elements.

- During a Start Sharing or Sync operation, all system administration tools sessions (System Administration Tool, Group Administration Tool, Desktop Tool, and MiXML sessions) on the local (master) node are terminated and subsequent sessions are blocked until the synchronization finishes. On the remote (slave) node, all System Administration Tool sessions remain active during the synchronization process. The user remains logged in with read-only access to the shared forms. All maintenance commands on the slave are disabled, but the administrator can log in, read data, and change data that is not shared.

- You can perform concurrent synchronizations. See About Concurrent Synchronizations for a more detailed overview of the conditions associated with synchronizing network elements concurrently.

- Check for SDS distribution updates and errors frequently and resolve all pending data distribution updates or errors on a regular basis. The number of SDS distribution updates cannot exceed 10,000. Any change that would create more updates than are available, displays an error dialog indicating that a "clean up" is required.

- Resolving SDS distribution updates and errors is a recommended best practice before upgrading system software. See the Network Upgrades Solutions Guide on Document Center.mitel.com for details.

- If you are running a mixed-release network, you may always have SDS errors on certain nodes, since different MCD/MiVoice Business releases may have database schema differences or that result in some data not being accepted on some nodes.

- When backing up or restoring system information on a System Data Synchronization network element, you must log in locally. The backup/restore applies only to the element you are logged in to. During a system backup/restore, the network element rejects all data update distribution attempts. See Performing Backups and Restores for more information.

- Consider assigning administrator rights to one person only, or to a select group of system administrators, to increase system security and further reduce the likelihood of errors.

- Where possible, maintain the same dimensioning settings and capacities between all the network elements that you configure to share data. The SDS system does not prevent data sharing between network elements that are dimensioned differently; however, maintaining parallel dimensioning prevents unnecessary SDS errors related to dimensioning discrepancies.

- Follow the proper programming procedures for setting up a data-sharing community, and for adding new network elements or multiple clusters to an existing community.

- You can use the SDS feature between elements that are running different versions of SDS software (for example between elements with 3300 ICP Release 6.0 software and Release 7.0 software). If you use the SDS feature between elements that have different versions of SDS software, the following rules apply to the sharing of data:

- Data sharing updates from a controller that has the later software version to a controller that has an older software version will result in any new fields being ignored on the controller with the older software version.

- Data sharing updates from a controller that has an older software version to a controller that has the later software version will cause the new fields on the controller with the later version to retain the current values, or in the case of add operation, the new field will be set to the default value for that field.

- If you have a network that includes controllers that are running different versions of SDS software, perform SDS operations from the controller that has the latest version of software.

- MiVoice Business Release 7.2 or up can share data with MiCollab Release 7.0 or up. The following limitations apply:

- All data-sharing nodes must be able to share with an MSL Server-type network element.

- Data-sharing with MiCollab server is not supported when multiple clusters exist. While sharing with an MSL Server network element type, creation of a second cluster is disallowed.

NOTE: If there is one cluster, but not all nodes are in the cluster, data-sharing with MiCollab is supported.

- MiVoice Business can data-share with only one MiCollab server in the network. Sharing with multiple MiCollab servers is not supported.

NOTE: To Start Sharing Data with a MiCollab server, MiCollab must be the only element selected in the Network Element form.

- Start Sharing Data with a MiCollab server is not allowed if the sharing scope for the following forms is other than "All Network Elements" or "Admin Group Members": User Roles, User and Services Templates, Service Hosting, User Definition. In addition, sharing scope for the User Definition and Service Hosting must be the same, and if it is "Admin Group Members", all cluster elements must be in the same admin group.

- If you start data sharing from a controller on a previous release with a controller on the MiVoice Business Release 9.0 or later, the SDS fails for the unsupported devices in the MiVoice Business Release 9.0.

- SDS Form Comparison, SDS Form Share, and SDS Synchronization with (from or to) earlier releases is not supported for the External FTP Server form.

Related Topics

- About Sharing and Synchronizing Data

- What Data Can Be Shared

- SDS Distribution Errors

- SDS Application Specific Guidelines and Limitations