问题描述

1. git 克隆 github 仓库，表现如下

$ git clone git@github.com:CANopenNode/CANopenNode.git
Cloning into 'CANopenNode'...
ssh: connect to host github.com port 22: Connection timed out
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

2. 参考github上的一个帖子，配置ssh的系统代理如下
   github上解决该问题的帖子
   win11配置：在.ssh目录下新建文件config, .ssh/config 内容如下：

Host github.com
User git
Hostname ssh.github.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa
Port 22
ProxyCommand connect -S 127.0.0.1:7890 %h %p

3. 重新克隆第一步的仓库，继续报错

$ git clone git@github.com:CANopenNode/CANopenNode.git
Cloning into 'CANopenNode'...
kex_exchange_identification: Connection closed by remote host
Connection closed by UNKNOWN port 65535
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

4. 继续搜索该问题，发现另一篇解决问题的帖子
   原贴
   修改 .ssh/config的内容如下

Host github.com
  User git
  Port 443
  Hostname ssh.github.com
  IdentityFile ~/.ssh/id_rsa
  TCPKeepAlive yes
  ProxyCommand connect.exe -S 127.0.0.1:7890 -a none %h %p

Host ssh.github.com
  User git
  Port 443
  Hostname ssh.github.com
  IdentityFile ~/.ssh/id_rsa
  TCPKeepAlive yes
  ProxyCommand connect.exe -S 127.0.0.1:7890 -a none %h %p

5. 重新克隆，问题得到解决，github仓库可以正常克隆，但是无法Ping github的问题仍未解决

问题分析

1. 猜想可能是因为代理配置的问题导致和github的通信出现错误，原因不清楚
2. 在终端ping github的时候发现解析出来的地址是20.205.243.166，使用Ip查询网站发现该ip在香港，猜想可能是因为DNS解析的问题导致解析出来的github地址无法访问，不过这个问题不重要，github能够克隆就行