在又一次登录ssh服务器时，突然就提示以下错误：

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@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
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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 is
99:86:21:af:e6:xx:27:xx:f0:18:31:9a:ff:52:05:xx.
Please contact your system administrator.
Add correct host key in /public/home/esystem/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /public/home/esystem/.ssh/known_hosts:1
ECDSA host key for 11.xx.xx.xx has changed and you have requested strict checking.
Host key verification failed.

解决方法：
清除.ssh/known_hosts文件，命令：

rm -rf ~/.ssh/known_hosts