HDFS
Scheme
HDFS is a named VFS connection. The scheme is the connection name, not hdfs:
cdp:///warehouse/db/table/part.parquet
See HDFS Connection.
hdfs://namenode:8020/… is a Spark/Hadoop FileSystem URI. Do not paste it into Hop File Input/Output on the local engine. See Paths and file systems on native Spark.
Configuration
Create an HDFS Connection in the metadata perspective. Install the hop-tech-hadoop marketplace plugin if it is not in your distribution.
For remote containers (OpenShift) use HttpFS or Knox. WebHDFS redirects data to DataNode HTTP ports, which those pods usually cannot reach.