Cut out summary from your post content here.
The remaining content of your post. root telnet登录失败
tail -20 /var/log/secure日志如下：
Apr 24 17:32:58 localhost login: pam_securetty(remote:auth): access denied: tty 'pts/1' is not secure !
Apr 24 17:33:03 localhost login: FAILED LOGIN 1 FROM localhost FOR root, Authentication failure
access denied: tty ‘pts/1’ is not secure !
方法一：所以将‘pts/1’添加到/etc/securetty中，即可实现telnet的root用户登录。
方法二：修改/etc/pam.d/remote，注释掉：auth required pam_securetty.so
1 #%PAM-1.0
2 #auth required pam_securetty.so
3 auth include system-auth