Hi @paulo_klein, Apache Spark by default request a delegation token for all 4 services: HDFS, YARN, Hive, and HBase. It is printed as a WARN message but it does no harm. It is captured due to the fact that no HBase jars are in the Spark classpath, hence, it's unable to get the HBase DelegationToken.
To fix this issue you start spark-shell or pyspark or spark-submit via
--conf spark.security.credentials.hbase.enabled=false
Example: # spark-shell --conf spark.security.credentials.hbase.enabled=false