Dynamic server selection (DSS) provides the CICS® Transaction Gateway administrator with several mechanisms for dynamically controlling the flow of work to CICS servers in a high availability operating environment. DSS also provides flexibility for deployment or change in environment.
DSS supports one-phase commit transactions, two-phase commit transactions, and ESI requests.
DSS is provided by a default CICS server, policy-based DSS definitions, logical CICS server definitions (deprecated), or a CICS request exit. You can use a default CICS server either on its own, or in combination with one of the other DSS mechanisms. Policy-based DSS, logical CICS server definitions (deprecated) and the CICS request exit cannot be used in combination with each other.