hadoop- cluster setup

1, single node setup

2,Setup passphraseless ssh

Now check that you can ssh to the localhost without a passphrase:
$ ssh localhost

If you cannot ssh to localhost without a passphrase, execute the following commands:
$ ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa
$ cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys

in slave:

1, scp ~/.ssh/id_dsa.pub XXX.XXX.XXX.XXX:/.ssh/.

2, cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys

so that master can login slave without inputting password by SSH. 

configure master and slaver in conf folder.

startup master, it is ok.