Linux ssh password-free login, points to pay attention to

Linux password-free login, the place to pay attention to

chmod 600 ~/.ssh/authorized_keys ## is very important, otherwise it will not take effect.

In addition :
/etc/ssh/ssh_config may also need to be modified accordingly
/etc/ssh/sshd_config RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile .ssh/authorized_keys