[root@li sh]# ssh 172.16.13.99

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[root@li sh]# scp ftp.sh 172.16.13.99://data/

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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
96:60:5a:ad:d3:52:9c:f0:34:c7:35:fc:e9:c8:22:01.
Please contact your system administrator.
Add correct host key in /root/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /root/.ssh/known_hosts:1
ECDSA host key for 172.16.13.99 has changed and you have requested strict checking.
Host key verification failed.
lost connection

解决办法：
[root@li sh]# rm -rf ~/.ssh/known_hosts
删除后再此尝试连接或者拷贝就可以了。