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The Information Server environment (in this topology) has all tiers deployed on a single host. This is not recommended as your DataStage Engine will have its licensed capacity reduced by the presence of other software components.
The MettleCI Workbench Service runs (in this topology) on the Windows-based DataStage Engine tier. This is because this service requires a shared filesystem with the MettleCI Unit Test Harness which can only be installed on the Engine tier.
The MettleCI Agent host also shares the same host, and will have actions invoked by your selected CI/CD build tool via the installed CD/CD agent. The MettleCI CLI is used by the CI/CD Agent to automate build and deployment activities. The MettleCI CLI and Agent need to be installed on a Windows host co-resident with a DataStage Client tier in order to enable the automation of the DataStage job compilation process, which requires the use of a Windows-based Client tier.
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