Subscription processing overview for data sets

You manage replication by creating subscriptions. Each subscription contains replication mappings that identify the data sets that you want to replicate as a consistent unit between the source and target sites.

Subscriptions are independent entities that you start, stop, and monitor in your replication environment. You can deploy multiple subscriptions to optimize throughput and maintain application boundaries. If an outage occurs in one application, the remaining applications can continue to replicate independently.

A subscription also specifies a target uniform resource locator (URL) for communication between the source and target servers. If you mark a subscription as persistent (the default), replication restarts for that subscription automatically when you start the Classic data server. If you stop a persistent subscription manually, you must restart it manually.

Manage subscriptions by using the Classic Data Architect client application. With the Classic Data Architect, you connect to the source and target servers to access information and metadata about Data Replication for VSAM. You then select source data sets to create replication mappings for your subscription. After you define the subscriptions, you can start and stop replication from the Classic Data Architect.

When you start replication, the source server automatically performs a Describe process, which sends information about your subscriptions and replication mappings to the target server. This process ensures that your subscription definitions, replication objects, and replication mappings are in a synchronized state when replication begins.