错误描述：The authenticity of host ‘servera (192.168.***.***)’ can’t be established.
ECDSA key fingerprint is SHA256:***********************************************************.
Are you sure you want to continue connecting (yes/no/[fingerprint])?
解决方法：ssh-copy-id -o StrictHostKeyChecking=n 用户名@192.168.***.***
之后按提示输入密码即可完成ssh免密设置！
