一、今天在使用SSH，连接远程服务器的时候，刚开始是没问题的。
后来阿里云主机重装了一下系统后，再也连不上了。一直报一个错。
$ ssh root@47.98.233.15@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!Someone could be eavesdropping on you right now (man-in-the-middle attack)!It is also possible that a host key has just been changed.The fingerprint for the ECDSA key sent by the remote host isSHA256:8hgJ8jpcBr1tm6HS72FpXwMrjba8MQqlqYJQLPB/Qf4.Please contact your system administrator.Add correct host key in /Users/wangdong/.ssh/known_hosts to get rid of this message.Offending ECDSA key in /Users/wangdong/.ssh/known_hosts:26ECDSA host key for 47.98.233.15 has changed and you have requested strict checking.Host key verification failed.
二、解决方法，看错误日志中有一句
Add correct host key in /Users/wangdong/.ssh/known_hosts to get rid of this message.
注意这个文件因环境不同而不一样，使用root用户则是：/root/.ssh/known_hosts
三、以编辑器的方式进入这个文件
vi /Users/wangdong/.ssh/known_hosts
四、将红线框部分删除掉 可理解为：删除远程ip对应的信息
五、再次进行远程连接
$ ssh root@47.98.233.15 The authenticity of host '47.98.233.15 (47.98.233.15)' can't be established.ECDSA key fingerprint is SHA256:8hgJ8jpcBr1tm6HS72FpXwMrjba8MQqlqYJQLPB/Qf4.Are you sure you want to continue connecting (yes/no)? yesWarning: Permanently added '47.98.233.15' (ECDSA) to the list of known hosts.root@47.98.233.15's password: Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.4.0-105-generic x86_64)* Documentation: * Management:* Support: /advantageWelcome to Alibaba Cloud Elastic Compute Service !root@iZbp17cj14ulhfrlj02rkaZ:~#
问题就解决了，原因是进行远程连接上，输入yes后，本机会将远程机器的信息，写到/Users/wangdong/.ssh/known_hosts文件中，如果远程重装系统了，本机一定要先清理掉远程机器的信息，才能再次连接成功。
