GitHub 异常——无法连接22端口：Connection timed out

问题描述
原因分析：
解决方案：
参考

问题描述

正常配置并使用使用SSH方式，使用以下命令git clone、git pull、git push，报错如下：

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.

原因分析：

表明SSH连接在尝试通过22端口连接到远程服务器时超时。这可能是由于网络环境、防火墙设置或代理配置等原因导致的（很可能端口22被防火墙或提供商阻止了）。

解决方案：

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

$ # This should also timeout
$ ssh -T git@github.com
ssh: connect to host github.com port 22: Connection timed out

$ # but this might work
$ ssh -T -p 443 git@ssh.github.com
Hi xxxx! You've successfully authenticated, but GitHub does not provide shell access.

$ # Override SSH settings

$ vim ~/.ssh/config

# Add section below to it
Host github.com
  Hostname ssh.github.com
  Port 443
  
$ ssh -T git@github.com
Hi xxxxx! You've successfully authenticated, but GitHub does not
provide shell access.

$ git clone git@github.com:xxxxxx/xxxxx.git my-awesome-proj
Cloning into 'my-awesome-proj'...
remote: Enumerating objects: 15, done.
remote: Counting objects: 100% (15/15), done.
remote: Compressing objects: 100% (14/14), done.
remote: Total 15 (delta 0), reused 15 (delta 0), pack-reused 0
Receiving objects: 100% (15/15), 22.90 KiB | 4.58 MiB/s, done.