I have two Ubuntu 16.04 servers running open source Hadoop 3.0. One is a NameNode, and the other is a DataNode. I have configured three .xml files on both servers to establish a cluster. The hduser on the NameNode can ssh into the DataNode. I have configured a workers file on the NameNode.
On the NameNode server I run this: bash start-all.sh On the DataNode I used the jps command before and after running the above bash script on the NameNode. This bash script on the NameNode starts the services on the datanode. I can tell because of the jps command's output. On the NameNode I run this: "hdfs dfsadmin -report" but I get this: "report: Call From NameNodeServer/10.10.10.10 to NameNodeServer:54310 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused"; The /etc/hosts files of both servers have no entry for 127.0.0.1 nor one for localhost. My .xml files refer to the correct NameNode server. I could manually ping it from both servers. There is no firewall between the servers blocking connectivity (as evidenced by start-all.sh successfully starting services). The problem does not happen with two RedHat servers in the cluster. What am I doing wrong with the two Ubuntu servers? Is this a bug?
