原WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

问题背景

之前配置好github ssh后可以正常使用，今天通过ssh，下载git代码时出现以下错误：

Cloning into 'geo'...
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    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 RSA key sent by the remote host is
SHA256:uNiVztksCsDhcc0u9e8BujQXVUpKZIDTMczCvj3tD2s.
Please contact your system administrator.
Add correct host key in /Users/havo/.ssh/known_hosts to get rid of this message.
Offending RSA key in /Users/havo/.ssh/known_hosts:19
Host key for github.com has changed and you have requested strict checking.
Host key verification failed.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
failed to run git: exit status 128

原因分析

因为服务器的ip发生变更了

第一次SSH连接时，会生成一个认证，储存在客户端/Users/havo/.ssh/known_hosts 文件中，但是如果服务器发生变化，认证就会出错。

解决方法

#ssh-keygen -R 这里为github的IP 例如：
ssh-keygen -R 20.205.243.166
# Host 20.205.243.166 found: line 19
/Users/havo/.ssh/known_hosts updated.