上周用ssh链接centos服务器也正常，今天链接服务器总是提示：
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 the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
41:75:21:36:52:55:44:6c:08:4e:e2:43:71:b2:fd:38.
Please contact your system administrator.
Add correct host key in /Users/user/.ssh/known_hosts to get rid of this message.
Offending key in /Users/user/.ssh/known_hosts:7
RSA host key for 127.0.0.1 has changed and you have requested strict checking.
Host key verification failed.
找到修复并解决方案：
ssh-keygen -R 127.0.0.1 IP换自己的服务器就可以了，简单吧！