I am trying to create a 2-node Hadoop cluster, following this guide. The one node is my Ubuntu laptop and the slave node, the 2nd one, is a virtualbox that also runs Ubuntu.
I am doing in the master node:
gsamaras@gsamaras:/home/hadoopuser/hadoop/sbin$ sudo ./start-dfs.sh 16/01/23 04:46:16 WARN hdfs.DFSUtil: Namenode for null remains unresolved for ID null. Check your hdfs-site.xml file to ensure namenodes are configured properly. Starting namenodes on [master] master: ssh: Could not resolve hostname master: Name or service not known root@localhost's password: root@localhost's password: localhost: Permission denied, please try again. If now I edit my /etc/hosts/ file to this:
127.0.0.1 localhost 127.0.1.1 gsamaras 127.0.1.1 slave-1 127.0.1.1 master // should I have this? the warning will leave, but I will still get a "permission denied". This question is exactly the same with mine's, but the answer did not help much. Any ideas please?
22 Answers
I am able to resolve the issue using below commands.
The following commands are used for generating a key value pair using SSH. Copy the public keys form id_rsa.pub to authorized_keys, and provide the owner with read and write permissions to authorized_keys file respectively.
$ ssh-keygen -t rsa $ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys $ chmod 0600 ~/.ssh/authorized_keys Try to give permission to your script file:
$ sudo chmod +x start-dfs.sh Then execute.
$ sudo bash start-dfs.sh 3