问题描述：
本地进行git pull时发现报错，具体报错信息如下：
Pushing to github.com:xxxxxxxx.git @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ 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:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx. Please contact your system administrator. Add correct host key in /xxxxxxxxx/.ssh/known_hosts to get rid of this message. Offending RSA key in /xxxxxxxxx/.ssh/known_hosts:1 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.
问题原因：
经排查，是github服务器升级，导致客服端known_hosts过期。原因如下： 第一次使用SSH连接时，会生成一个认证，储存在客户端的known_hosts中，远程git服务器更新时，本地known_hosts过期。
SSH会把每个曾经访问过的Git服务器的公钥记录在/Users/xx/.ssh/known_hosts文件中，当下次访问时会核对公钥，如果和上次的记录不同，SSH就会发出警告。
解决办法：
把本地缓存的 hosts 删除就好了，具体操作如下：
进入到对应的.ssh目录下，查看known_hosts
ssh-keygen -l -f ~/.ssh/known_hosts
ssh-keygen -R 服务器端的ip地址（上面warnning提示中对应序号的ip地址）
出现提示：
此时 重新进行git pull操作，出现提示：
输入yes，会自动更新known_hosts。
然后就可以正常进行git操作了。
- IDENTIFICATION 错误 CHANGED REMOTE HOSTidentification错误changed remote identification warning changed remote identification changed warning remote 密钥identification changed remote identification错误warning changed identification warning changed办法 identification warning changed服务器 identification warning changed方法 identification changed代码github quot ssh_exchange_identification host identification