通过 SSH 连接 群晖 时出现类似如下报错且无法正确建立连接：

WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!
Host key verification failed

问题现象：

lsj@Mac-Pro ~ % ssh 192.168.10.251
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    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:QnnL5H5ErnkpQbtDXFN3n8Z4GFBNgMKZevhJU1Oa5cs.
Please contact your system administrator.
Add correct host key in /Users/lsj/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /Users/lsj/.ssh/known_hosts:4
Host key for 192.168.10.251 has changed and you have requested strict checking.
Host key verification failed.

问题原因：

服务器的公钥(public key)发生了变化（比如重装了系统或重装了openssh服务），而客户端存储的信息没有发生变化

使用 OpenSSH 连接服务器会把你每个你访问过计算机的公钥(public key)都记录在 ~/.ssh/known_hosts 文件中。当下次访问相同计算机时，OpenSSH会核对公钥。如果公钥不同，OpenSSH会发出警告，避免你受到DNS Hijack之类的攻击。

解决方案：

ssh-keygen -f "/User/lsj/.ssh/known_hosts" -R 192.168.10.251