Engine tier

The engine tier is the logical group of engine components, communication agents, and so on. The engine runs jobs and other tasks for product modules.

Several product modules require the engine tier for certain operations. You install the engine tier components as part of the installation process for these product modules. The following product modules require the engine tier:
  • IBM® InfoSphere® DataStage®
  • IBM InfoSphere Information Analyzer
  • IBM InfoSphere Information Services Director
  • IBM InfoSphere QualityStage®
  • IBM InfoSphere Information Server istool command line. The istool framework is installed on the engine tier and client tier. Commands for InfoSphere Information Analyzer are installed on the engine tier only when the product is installed.

IBM InfoSphere FastTrack, Information Governance Catalog, and IBM Glossary Anywhere do not require an engine tier.

AIX® Linux: The following configurations are supported:
  • Multiple engines, each on a different computer, all registered to the same InfoSphere Information Server services tier.
  • Multiple engines on the same computer. In this configuration, each engine must be registered to a different services tier. This configuration is called an ITAG installation.

Microsoft Windows: Only one InfoSphere Information Server engine can be installed on a single computer.

The installation program installs the following engine components as part of an engine tier:
InfoSphere Information Server engine
Runs tasks or jobs such as discovery, analysis, cleansing, or transformation. The engine includes the server engine and parallel engine and other components that make up the runtime environment for InfoSphere Information Server and its product components.
ASB agents
Java™ processes that run in the background on each computer that hosts an InfoSphere Information Server engine tier. When a service that runs on the services tier receives a service request that requires processing by an engine tier component, the agents receive and convey the request.

AIX Linux: The agents run as daemons that are named ASBAgent.

Microsoft Windows: The agents run as services that are named ASBAgent.

ASB agents include:

Connector access services agent
Conveys service requests between the ODBC driver components on the engine tier and the connector access services component on the services tier.
InfoSphere Information Analyzer agent
Conveys service requests between the engine components on the engine tier and the InfoSphere Information Analyzer services component on the services tier.
InfoSphere Information Services Director agent
Conveys service requests between the engine components on the engine tier and the InfoSphere Information Services Director services component on the services tier.
ODBC drivers

The installation program installs a set of ODBC drivers on the engine tier that works with InfoSphere Information Server components. These drivers provide connectivity to source and target data.

Resource Tracker

The installation program installs the Resource Tracker for parallel jobs with the engine components for InfoSphere DataStage and InfoSphere QualityStage. The Resource Tracker logs the processor, memory, and I/O usage on each computer that runs parallel jobs.

dsrpcd (DSRPC Service)
Allows InfoSphere DataStage clients to connect to the server engine.
AIX Linux: This process runs as a daemon (dsrpcd).
Microsoft Windows: This process runs as the DSRPC Service.
Job monitor
A Java application (JobMonApp) that collects processing information from parallel engine jobs. The information is routed to the server controller process for the parallel engine job. The server controller process updates various files in the metadata repository with statistics such as the number of inputs and outputs, the external resources that are accessed, operator start time, and the number of rows processed.
Operational MetaData monitor
A Java application (OMDMonApp) that processes the operational metadata XML files that are generated by job runs if the collection of operational metadata is enabled. The information in the XML files is stored in the metadata repository, and the XML files are deleted.
DataStage engine resource service
Microsoft Windows: Establishes the shared memory structure that is used by server engine processes.
DataStage Telnet service
Microsoft Windows: Allows users to connect to the server engine by using Telnet. Useful for debugging issues with the server engine. Does not need to be started for normal InfoSphere DataStage processing.
MKS Toolkit
Microsoft Windows: Used by the InfoSphere Information Server parallel engine to run jobs.

The following diagram shows the components that make up the engine tier. Items marked with asterisks (*) are only present in Microsoft Windows installations.

Figure 1. Engine tier components
This figure is described in the surrounding text.
Note: InfoSphere Metadata Integration Bridges are installed only on the client tier, not on the engine tier.