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.

SSH远程访问服务器，报错

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.

可能是你重装系统后使用原来的密钥继续访问，为防止中间人攻击，只需要删除原来的密钥对，重建密钥对并绑定到当前的服务器，SSH使用新的密钥对访问就可以了。