SSH localhost is not supported when hadoop is installed.

When installing hadoop, you need to ensure that SSH localhost can be logged on without entering a password. Today, I will always lose the password after installing it on a public server according to the tutorial. I don't know what the problem is. Google will find this article.Article:

Http://stackoverflow.com/questions/7439563/hard-how-to-ssh-localhost-without-password

In the past, the authorized_keys file had strict permission requirements.Only the read permission is required.So you only need to solve the problem after chmod 644 authorized_key!