SSH不能连接并提示REMOTE HOST IDENTIFICATION HAS CHANGED解决方法：
如果提示信息如下：
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@ WARNING: REMOTE HOST IDENTIFICATION HASCHANGED! @
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IT IS POSSIBLETHAT SOMEONE IS DOING SOMETHING NASTY!
Someone couldbe eavesdropping on you right now (man-in-the-middle attack)!
It is alsopossible that the RSA host key has just been changed.
Thefingerprint for the RSA key sent by the remote host is
3c:3c:4b:f9:37:2f:76:61:15:65:e5:80:1b:db:a7:3c.
Please contactyour system administrator.
Add correcthost key in /root/.ssh/known_hosts to get rid of this message.
Offending keyin /root/.ssh/known_hosts:15
RSA host keyfor 192.168.0.252 has changed and you have requested strict checking.
Host keyverification failed.
rsync:connection unexpectedly closed (0 bytes received so far) [sender]
rsync error:error in rsync protocol data stream (code 12) at io.c(359)
的解决办法：
vi /root/.ssh/known_hosts
找到要连接的主机的ip，把它的那行所有信息删除（就是一行）