[root@localhost   wj]# rpm -qa | grep ssh

libssh3-1.4.2-1.el6.i686

openssh-askpass-5.3p1-94.el6.i686

openssh-server-5.3p1-94.el6.i686

openssh-clients-5.3p1-94.el6.i686

openssh-5.3p1-94.el6.i686

[root@localhost   wj]# service sshd status

openssh-daemon   (pid  1634) 正在運行...

[root@localhost   wj]#

[root@localhost   wj]# ssh root@192.168.0.119

The authenticity   of host '192.168.0.119 (192.168.0.119)' can't be established.

RSA key   fingerprint is 36:20:c9:ab:88:1f:47:74:1b:f1:d7:47:55:e0:14:7c.

Are you sure you   want to continue connecting (yes/no)? yes

Warning:   Permanently added '192.168.0.119' (RSA) to the list of known hosts.

root@192.168.0.119's password:

Last login: Fri   Aug 10 14:57:45 2018

already login

[root@localhost   ~]# exit

logout

Connection to   192.168.0.119 closed.

[root@localhost   wj]# gedit /etc/ssh/sshd_config

PermitRootLogin no    //這里默認是yes，而且已經被注釋掉了。取消注釋，改為no

[root@localhost   wj]# service sshd restart           //重啟服務

停止 sshd：                                                  [確定]

正在啟動 sshd：                                            [確定]

[root@localhost   wj]#

[root@localhost   wj]# ssh root@192.168.0.119

root@192.168.0.119's password:

Permission denied, please try again.

[root@localhost   wj]# gedit /etc/ssh/sshd_config

AllowUsers david    //允許david登錄

[root@localhost   wj]# service sshd restart           //重啟服務

停止 sshd：                                                  [確定]

正在啟動 sshd：                                            [確定]

[root@localhost   wj]#

[root@localhost   wj]# ssh weijie@192.168.0.119

weijie@192.168.0.119's password:

Permission denied, please try again.

[root@localhost   wj]# ssh david@192.168.0.119

david@192.168.0.119's password:

Last login: Wed Aug 15 17:12:59 2018 from 192.168.0.112

already login