centos免密登录

ssh root@127.0.0.1  需要登陆密码

ssh-keygen 生成公钥和私钥     可以去.ssh 查看是否有两个文件    id_rsa  id_rsa.pub

ssh-copy-id root(注释：访问者的密码)@127.0.0.1 复制公钥到远程服务器   可以去.ssh 查看是否有  authorized_keys

ssh root@127.0.0.1  不需要登陆密码了

例：

[root@localhost ~]# ls -a
.                .bash_logout   .config  Documents      initial-setup-ks.cfg  Pictures  Templates
..               .bash_profile  .cshrc   Downloads      .local                Public    Videos
anaconda-ks.cfg  .bashrc        .dbus    .esd_auth      Music                 .ssh      .Xauthority
.bash_history    .cache         Desktop  .ICEauthority  original-ks.cfg       .tcshrc
[root@localhost ~]# cd .ssh
[root@localhost .ssh]# ls
id_rsa  id_rsa.pub

[root@localhost .ssh]# ssh-copy-id root@127.0.0.1
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@127.0.0.1's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@127.0.0.1'"
and check to make sure that only the key(s) you wanted were added.

[root@localhost .ssh]# ls
authorized_keys  id_rsa  id_rsa.pub  known_hosts
[root@localhost .ssh]#