New to Hadoop-SSH communication

[Automation Me]

Hello,

I am new to Hadoop and trying to install multinode cluster on ubuntu VM's.I
am not able to communicate between two clusters using SSH.

My host file:

127.0.1.1 Master
127.0.1.2 Slave

The following changes i made in two VM's

1.Updated the etc/hosts file in two vm's

on Master VM
 i did SSH keygen and trying to copy the key into Slave

ssh-keygen -t rsa -P ""
       cat $HOME/.ssh/id_rsa.pub >> $HOME/.ssh/authorized_keys
       ssh-copy-id -i $HOME/.ssh/id_rsa.pub slave@ubuntu.

When i login into master and slave  and check

master@ubuntu>Hostname it says UBUNTU
slave@ubuntu>Hostname it says UBUNTU


Could you assist me on this?

Thanks
Annt