While installing hadoop in my local machine , i got following error
ssh -vvv localhost 
OpenSSH_5.5p1, OpenSSL 1.0.0e-fips 6 Sep 2011 
debug1: Reading configura         
        Check if this port is open. Maybe your SSH demon is not running. See if sshd is running. If not, then start it.
You may should edit your /etc/hosts.  For example if my hostname is ub0, but the hostname in /etc/hosts is localhost, it may occur 
connect to host ub0 port 22: Connection refused
Because the hostname in /etc/hosts is localhost not ub0.
So, you should be careful the hostname when building up distributed clusters.
Check file /etc/ssh/sshd_config for Port number. Make sure it is 22.
Remove SSH with the following command:
sudo apt-get remove openssh-client openssh-server
Install SSH again with:
sudo apt-get install openssh-client openssh-server
It will solve your problem.