ssh-keygen -t rsa

一直按enter

chmod 0700 /root/.ssh

chmod 0600 /root/.ssh/*

scp -P 22 /root/.ssh/id_rsa.pub root@1.2.3.4:.ssh/

输入密码

上传后

ssh -p 22 root@1.2.3.4

输入密码登陆

chmod 0700 /root/.ssh

cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized.key

chmod 0600 /root/.ssh/authorized.key

exit

最后ssh -p 22 root@1.2.3.4    或者  ssh -p 22 root@1.2.3.4 -i /root/.ssh/id_rsa