@joe john Have you checked trying to wget http://public-repo-1.hortonworks.com/HDP/centos7/2.x/updates/2.5.3.0/hdp.repo from the server? It could be a case of firewall issues. Also, can you post what error is shown next to the red exclamation? ... View more

@Anas A 1) HDP is a stack that is maintained by Hortonworks. It is a collection of services and versions of the services certified by Hortonworks to work together as a hadoop system. With a version of HDP "stack", you will have a recommended set of versions of services installed. You can see the growth of the HDP stack in the diagram titled "Ongoing innovation in Apache", here : http://hortonworks.com/products/data-center/hdp/ 2) To use HDP repo you don't need an enterprise license. HDP is completely open source 3) Before starting off things in a production system, you may want to check install using sandbox and get familiar with HDP: http://hortonworks.com/hadoop-tutorial/learning-the-ropes-of-the-hortonworks-sandbox/ and then go ahead and look at : https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.3.0/bk_installing_manually_book/content/ch_getting_ready_chapter.html To get a starting point into HDP docs, look at : http://hortonworks.com/downloads/#data-platform and http://docs.hortonworks.com/index.html -- This has docs for every version of HDP and ambari ... View more

@Ludovic Janssens Please refer to the following doc : https://docs.hortonworks.com/HDPDocuments/Ambari-2.1.2.1/bk_Ambari_Users_Guide/content/_decommissioning_masters_and_slaves_.html and https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.3.0/bk_Sys_Admin_Guides/content/ref-b50b4ee6-0d7b-4b86-a06f-8e7bac00810f.1.html to understand #1 To answer #2, Yes the physical data will remain in the worker node (unless you delete the node). You will need to rebalance once you recommission your node. Refer point #7 here : https://acadgild.com/blog/commissioning-and-decommissioning-of-datanode-in-hadoop/ Hope this helps! ... View more

Hi @Andrew Watson, Please refer the following community question for the same : https://community.hortonworks.com/questions/49340/how-do-i-change-namenode-and-datanode-dir-for-an-e.html#comment-49804. This has a certified approved answer. You can also check : https://community.hortonworks.com/articles/2308/how-to-move-or-change-the-hdfs-datanode-directorie.html Hope this helps! ... View more