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Custom services in Apache Ambari can be packaged and installed in many ways.  Ideally, they should all be packaged and installed in the same manner.  This document describes how to package and install custom services using Extensions and Management Packs.  Using this approach, the custom service definitions do not get inserted under the stack versions services directory.  This keeps the stack clean and allows users to easily see which services were installed by which package (stack or extension).

Management Packs

A management pack is a mechanism for installing stacks, extensions and custom services.  A management pack is packaged as a tar.gz file which expands as a directory that includes an mpack.json file and the stack, extension and custom service definitions that it defines.

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      "source_dir": "extensions"

    }

  ]

}

Extensions

An extension is a collection of one or more custom services which are packaged together. Much like stacks, each extension has a name which needs to be unique in the cluster. It also has a version folder to distinguish different releases of the extension which go in the resources/extensions folder with <name>/<version> sub-folders.

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