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 fingerp

[root@k8s-master ~]# scp /etc/sysctl.d/k8s.conf root@192.168.30.23:/etc/sysctl.d/k8s.conf
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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
SHA256:wtnYVEKUFR4FOW7aRS8HiwFnTv5CmIUuOGfOyuJNQe8.
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 192.168.30.23 has changed and you have requested strict checking.
Host key verification failed.
lost connection
用scp 命令传输的时候出现以上报错

[root@k8s-master ~]# echo >~/.ssh/known_hosts     将你当前用户根目录下的.ssh/known_hosts文件清空或删除）
[root@k8s-master ~]# rm -fr ~/.ssh       （删除本机的密匙）
[root@k8s-master ~]# scp /etc/sysctl.d/k8s.conf root@192.168.30.23:/etc/sysctl.d/k8s.conf
The authenticity of host '192.168.30.23 (192.168.30.23)' can't be established.
ECDSA key fingerprint is SHA256:wtnYVEKUFR4FOW7aRS8HiwFnTv5CmIUuOGfOyuJNQe8.
ECDSA key fingerprint is MD5:78:38:1c:08:20:bd:90:9e:0f:f3:81:22:eb:a3:88:4a.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.30.23' (ECDSA) to the list of known hosts.
root@192.168.30.23's password:
k8s.conf