往阿里云服务器上复制文件，显示报错，
报错信息如下@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 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 ED25519 key sent by the remote host is SHA256:St/NTeKZ4+EdcX9NS4ipaw9jx+6gxzoKwjf+Nic4x18. Please contact your system administrator. Add correct host key in /Users/hfwas/.ssh/known_hosts to get rid of this message. Offending ECDSA key in /Users/hfwas/.ssh/known_hosts:3 Host key for 101.200.178.253 has changed and you have requested strict checking. Host key verification failed. lost connection截图如下 问题原因
刚才阿里云服务器重装了系统，导致所有与原系统建立过ssh连接的系统都无法再建立连接，因为在于原系统建立首次连接时，双方相互记录了对方的公钥（ssh基于非对称密钥技术），在ssh服务主机重装系统后，公钥改变了，任以旧版本公钥的主机自然是无法与新系统连接的。
解决办法在 ~/.ssh下删除 known_hosts即可。执行rm known_hosts
再次尝试传输文件，显示传输成功，没有报错。
