在一次常规vps远程备份，备份失败，提示”REMOTE HOST IDENTIFICATION HAS CHANGED”。远程主机标识被改。后通过查询各种资料后解决失败问题。这里顺道记录解决方法。
在源服务器执行网站备份脚本，提示如下报错信息：
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ 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 ECDSA key sent by the remote host is 3b:ab:8b:a6:2e:bf:4b:aa:4c:82:1e:6e:66:c1:a9:00. 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:3 ECDSA host key for 107.173.149.75 has changed and you have requested strict checking. Host key verification failed. rsync: connection unexpectedly closed (0 bytes received so far) [sender] rsync error: unexplained error (code 255) at io.c(226) [sender=3.1.2]
在源vps上，将其/root/.ssh/known_hosts编辑，删除备份vps IP的ECDSA host key，保存再次执行即可实现通信。
使用ssh-keygen命令删除旧密钥,
$ ssh-keygen -R [主机名| IP地址]