Hi Guys, Thanks a lot for your help. Just to summarize the issue so that someone else knows what to do: If using HDP sandbox 2.4, for the tutorial "A Lap Around Apache Spark", there is no need to install spark, everything is in. When I had problem starting spark, it was because there is another spark instance running. Started because I was running the "Spark on Zeppelin" tutorial. To stop the spark session, use the "yarn application -list" and "yarn application -kill" command to kill of other spark on yarn sessions. All is well now. Takes again for your help. ... View more