前言
昨天在拉取github上面的项目报错了，有好几个月没用github了，命令如下：
git clone git@github.com:zhszstudy/git-test.git
报错信息：
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.
我重新设置github上的ssh key，梯子也开了还是报这个错，换成https链接拉取也报错，查阅资料发现，此错误信息为不能通过 22 端口连接到 GitHub
解决方法
- 执行以下命令：
ssh -T git@github.com
如果出现连接超时就意味着不能通过22端口连接：
ssh: connect to host github.com port 22: Connection timed out
- 将 SSH 连接的端口更改为 443：
ssh -T -p 443 git@ssh.github.com
出现以下信息，表示通过 443 端口成功进行了身份验证，但 GitHub 不提供 shell 访问权限：
Hi xxxx! You've successfully authenticated, but GitHub does not provide shell access.
如果出现以下信息，则需要回复yes，如果输出上面的信息表示成功：
The authenticity of host '[ssh.github.com]:443 ([20.205.243.160]:443)' can't be established.
ED25519 key fingerprint is SHA256:+DiY3wvvV6TuJJhbpZisF/zLDA0zPMSvHdkr4UvCOqU.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])?
Host key verification failed.
- 在密钥目录下新建文件config，编写配置覆盖 SSH 设置：
Host github.com
Hostname ssh.github.com
Port 443
- 重新执行以下命令：
ssh -T git@github.com
出现以下信息表示成功：
Hi xxxxx! You've successfully authenticated, but GitHub does not provide shell access.
- 重新拉取项目，可以看到已经拉取成功了：
$ git clone git@github.com:zhszstudy/git-test.git
Cloning into 'git-test'...
remote: Enumerating objects: 118, done.
remote: Counting objects: 100% (118/118), done.
remote: Compressing objects: 100% (29/29), done.
remote: Total 118 (delta 12), reused 109 (delta 11), pack-reused 0 (from 0)
Receiving objects: 100% (118/118), 7.90 KiB | 476.00 KiB/s, done.
Resolving deltas: 100% (12/12), done.
