ssh验证的机制问题

stonerose

两台服务器简称A和B
A机使用ssh登录到B机，之后B机重新安装，A机再次使用ssh登录时提示：
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    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 the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
98:70:c8:db:51:23:9d:43:5a:74:23:48:43:ba:fd:05.
Please contact your system administrator.
Add correct host key in /root/.ssh/known_hosts to get rid of this message.
Offending key in /root/.ssh/known_hosts:7
RSA host key for 10.0.2.15 has changed and you have requested strict checking.
Host key verification failed.
使用C机ssh登录到B机一切正常，请问如何解决这种问题。

Forget&Reme

vi /root/.ssh/known_hosts, delete the line of 10.0.2.15.try again