Hi, I have recently installed HDP 3.0. I was trying to work on below tutorial, https://hortonworks.com/tutorial/nifi-in-trucking-iot-on-hdf/ Since Apache nifi was needed, as per the instructions provided in below link, i implemented the steps. https://github.com/orendain/trucking-iot/tree/hadoop-summit-2017 When i arrived at below step, the SSH command resulted in an error, 'Connection refused' Once the container is created, SSH into the HDF sandbox: ssh root@sandbox-hdf.hortonworks.com -p 12222 # password: greenhadoop I understood that i need to install HDF sandbox. So i tried to upgrade Ambari and HDP before upgrading HDF sandbox to the whole set up. Here i followed below steps as mentioned: https://docs.hortonworks.com/HDPDocuments/HDF3/HDF-3.4.1.1/installing-hdf-on-hdp/content/hdf-upgrade-ambari-and-hdp.html The above link was helpful in some places. In some places, i was running to permission denied error. This messed up the whole installation (if i am not wrong) leading to lot of critical alerts in Ambari. Finally i thought of getting the Whole HDP uninstalled and was thinking about starting everything from the scratch. The pain point is when uninstalling HDP. As found in below links; i referred and tried to uninstall HDP so that i can start with a new set of installtion for HDP and HDF afresh. https://community.hortonworks.com/questions/1110/how-to-completely-remove-uninstall-ambari-and-hdp.html https://community.hortonworks.com/articles/97489/completely-uninstall-hdp-and-ambari.html Above links have several breaking points and I was not able to successfully complete the uninstall. Now i am stranded and not able to proceed further with my POC. Appreciate if someone can help with you inputs to start everything afresh. All i am planning to do is to perform a POC and learn NIFI integration with Kafka. I appreciate your feedback. Thanks in advance. Regards, MK ... View more