ssh-keygen –t rsa
Then press the Enter key all the way, and finally wrote the id_rsa.pub authorized_keys, the command is as follows:
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
In hadoop user, you need to give permission to 600 authorized_keys, otherwise invalid password-free login. Other nodes only need to use ssh-keygen -t rsa command to produce a corresponding public key, and then appended to id_rsa.pub authorized_keys nna nodes in each node. Finally, the authorized_keys file under nna node via scp command, distributed to each node ~ / .ssh / directory. Contents are as follows:
# This is an example of the node to NNS scp ~ / .ssh / authorized_keys hadoop @ nns: ~ / .ssh /
Then use the ssh command to log in to each other, to see whether to implement a password-free login, the login command is as follows:
# In this example node nns nns SSH
If the login process wood prompted to enter the password, it means that the password configured successfully.
Note: / home / hadoop permissions to 700
permissions .ssh folder also 700
authorized_keys file permissions to 600
otherwise, can not be achieved free login password.
rm ~/.ssh/authorized_keys
ls .ssh
cp authorized_keys ~/.ssh/
chmod 600 ~/.ssh/authorized_keys