Hello everybody,
I set up a a Flink (1.12.1) and Hadoop (3.2.1) cluster on two machines.
The job should store the checkpoints on HDFS like so:
```java
StreamExecutionEnvironment env =
StreamExecutionEnvironment.getExecutionEnvironment();
env.enableCheckpointing(15000, CheckpointingMode.EXACTLY_ONCE);
env.setStateBackend(new FsStateBackend("hdfs://node-1:9000/flink"));
```
Unfortunately, the JobManager throws
```
org.apache.flink.core.fs.UnsupportedFileSystemSchemeException: Could not
find a file system implementation for scheme 'hdfs'. The scheme is not
directly supported by Flink and no Hadoop file system to support this
scheme could be loaded. For a full list of supported file systems,
please see
https://ci.apache.org/projects/flink/flink-docs-stable/ops/filesystems/.
// ...
Caused by:
org.apache.flink.core.fs.UnsupportedFileSystemSchemeException: Hadoop is
not in the classpath/dependencies.
```
and I don't understand why.
`echo $HADOOP_CLASSPATH` returns the path of Hadoop libraries with
wildcards. Flink's JobManger prints the classpath which includes
specific packages from these Hadoop libraries. Besides that, Flink
creates the state directories on HDFS, but no content.
Thank you for any advice,
Matthias
