Data router (DX)

IBM Z Workload Scheduler subtasks communicate with each other within the system and among systems. The data router (DX) subtask routes data from the components that send data to those that receive data. The following IBM Z Workload Schedulersubtasks send data for processing to other subtasks via the DX subtask:
  • Event reader subtask (sends events)
  • Event writer subtask (sends events)
  • Workstation analyzer subtask (sends JCL, commands, release requests, and WTO messages)
  • Network communication function (CB) subtask.
The following IBM Z Workload Scheduler subtasks receive data from the DX subtask:
  • Event manager subtask (processes events)
  • Submit subtask (submits JCL)
  • Network communication function (CB) subtask.

When a sending component transmits data to a receiving component, the sending component puts the data on a router queue for processing by the DX subtask. The subtask can send the data to a component on the same IBM Z Workload Scheduler system as the sending component or to a component on another IBM Z Workload Scheduler system.

The DX subtask passes the data directly to the receiving component when the sending and receiving components reside on the same system. When the data is sent to another IBM Z Workload Scheduler system, the DX subtask transmits the data to the DX subtask on that system. The receiving DX subtask then passes that data to the receiving component on that system. One of the following methods is used to transmit data between systems:
  • Cross-system coupling facility (XCF) communication links
  • SNA communication links
  • TCP/IP communication link
Sometimes other components are involved in routing data between IBM Z Workload Scheduler systems:
  • When you are using SNA communication links, the network communication function (CB) performs the transmission.
  • When an operation is ready to be started on a workstation that specifies a user-defined destination, the DX subtask queues the request to the external router (EX) subtask. The EX subtask calls the operation-initiation exit, EQQUX009, to handle communications with the user-defined destination.