hadoop/README.md

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# Apache Hadoop base image

This is the definition of the Apache Hadoop base image. It doesn't use any Hadoop distribution just the scripts to run any Hadoop from source or from a prebuild package.

## Build

To create a local version of this image use the following command:

```
docker build -t apache/hadoop-runner .
```

## Usage

Do a full build on Apache Hadoop trunk with the `hdds` profile enabled.
```
mvn clean install package -DskipTests -Pdist,hdds -Dtar -Dmaven.javadoc.skip=true
```

Then start HDDS services with `docker-compose`.

```
cd hadoop-dist/target/compose/ozone
docker-compose up -d
```

## Troubleshooting

If `docker-compose` fails to work, check that the `hadoop-dist/target/compose/ozone/.env` file exists and has a line like the following (the exact version number may be different):
```
    HDDS_VERSION=0.2.1-SNAPSHOT
```