登录ssh的时候,出现错误：
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    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 the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
xxxxxxxxxxxxxxxxxxx.
Please contact your system administrator.
Add correct host key in /root/.ssh/known_hosts to get rid of this message.
Offending key in /root/.ssh/known_hosts:5
RSA host key for xx.xx.xx.xx has changed and you have requested strict checking.
Host key verification failed.

上网查了一下，删掉或者移动/root/.ssh/known_hosts文件就可以了
#rm /root/.ssh/known_hosts

或者

#mv /root/.ssh/known_hosts /tmp
 

“Offending key in /root/.ssh/known_hosts:5”
据说删除文件中第五行也行，我没试过