Choosing a Replication Method

DATABridge offers several ways to clone a DMSII database. You can use any of these methods while the DMSII database is in operation and being updated.

Cloning is the one-time process of generating a complete snapshot of a data set to another file. Cloning creates a static picture of a dynamic database. DATABridge uses the DMSII data sets and the audit trail to ensure that the cloned data represents a synchronized snapshot of the data sets at a quiet point, even though other programs may be updating the database concurrently. DATABridge clones only those data sets you specify.

Cloning is one phase of the database replication process. The other phase is tracking (or updating), which is the integration of database changes since the cloning.

Use this

For

Snapshot Accessory

Single DMSII data extraction or infrequent clones of a database.

Snapshot Accessory clones all of the selected data sets each time you run it (not just the changes). Because cleanup and consolidation takes place on the host, Snapshot Accessory uses more host resources than Span Accessory. See Span and Snapshot Compared for a comparison of these accessories. For more information about Snapshot, see How the Snapshot Accessory Works.

Span Accessory

A primary database that has frequent changes.

Span Accessory gathers only changes to the primary database when it updates the secondary database. For details, see How the Span Accessory Works. See Span and Snapshot Compared for a comparison of these accessories.

Note: This accessory does not apply the fixup records. You must combine these changes with the extraction in order to extract and update the data. Additionally, the files must be manually transported to use them on a secondary system.

The following methods require DATABridge Host and additional DATABridge components.

Use this

For

Server Accessory and DATABridge Client

Cloning and transporting DMSII data and subsequent updates to a remote client (secondary database). For more information, see the DATABridge Client Administrator's Guide and the DATABridge Client Console Help.

DATABridge Enterprise Server and DATABridge Client

Cloning and transporting DMSII data and subsequent updates to a remote client (secondary database). Use this method to reduce mainframe usage and related expense by moving all cloning and filtering to a Windows system. This method is similar to the preceding method except that Enterprise Server performs the functionality of the Server Accessory. For more information, see the Help included with the DATABridge Enterprise Server.

DATABridge FileXtract

Replicating flat files.

For more information, see the DATABridge FileXtract Administrator's Guide.

DMSII Client or DATABridge Twin

Replication to a Unisys MCP Server (ClearPath NX, LX or A Series mainframe). For more information, see the DATABridge DMSII Client Administrator's Guide or the DATABridge Twin Administrator's Guide.