The concept of a data group is used to perform replication activities. A data group is a logical grouping of database files, library-based objects, IFS objects, DLOs, or a combination thereof that defines a unit of work by which MIMIX replication activity is controlled. A data group may represent a journal, an application, a set of one or more libraries, or all of the critical data on a given system. Application environments may define a data group as the objects journaled to a specific journal or as a specific set of files and objects. For example, the R/3 environment defines a data group as a set of SQL tables that all use the same journal and which are all replicated to the same system. Users can start and stop replication activity by data group, switch the direction of replication for a data group, and display replication status by data group.
By default, data groups support replication from both the system journal and the user journal. Optionally, you can limit a data group to replicate using only one replication path. The parameters in the data group definition identify the direction in which data is allowed to flow between systems and whether to allow the flow to switch directions. You also define the data to be replicated and many other characteristics the replication process uses on the defined data. The replication process is started and ended by operations on a data group.
A data group entry identifies a source of information that can be replicated. Once a data group definition is created, you can define data group entries, which are called selection rules within the Assure Unified Interface. MIMIX uses the data group entries that you create during configuration to determine whether a journal entry should be replicated. If you are using both user journal and system journal replication, a data group can have any combination of entries for files, IFS objects, library-based objects, and DLOs.
When a data group is configured to use journal-centric configuration for specific object types journaled to the user journal, information about what objects journaled to that journal is stored internally. Data group entries are only needed for identifying journaled objects that require name mapping between systems, that have differences to ignore during auditing in a data distribution environment, that you do not want to replicate through the user journal for performance reasons, for identifying journaled objects to exclude from replication, and to identify objects that cannot be journaled for system journal replication.