ssh connect to host github.com port 22 Connection refused

背景：电脑(win10)重装后，提交(push)代码提示ssh: connect to host github.com port 22: Connection refused，无法进行代码提交。

在windows上更新了git仓库中的代码后，由于我前阵子刚重装了系统，ssh key都是重新生成的，而且我本机上有一个gitlab账号，有一个github账号，都放在~/.ssh目录下，具体文件如下：

上图中的yomige_rsa就是我github账户的私钥，然后就是我提交代码时候的报错信息如下：

$ git push origin master
ssh: connect to host github.com port 22: Connection refused
fatal: Could not read from remote repository.

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

解决上述问题的方法是更改~/.ssh/config文件，将github.com的HostName更改为下列内容，并指定端口，内容如下：

#default gitlab
    Host gitlab
      HostName gitlab
      PreferredAuthentications publickey
      IdentityFile ~/.ssh/id_rsa    

    Host github.com
      HostName ssh.github.com
      Port 443
      PreferredAuthentications publickey
      IdentityFile ~/.ssh/yomige_rsa

==============2016年7月26日更新================

后来发现，我这里无法进行连接的原因竟是我在hosts文件里加的github的ip无法访问了，我就把hosts文件里关于github的ip全部删掉了，然后更改~/.ssh/config文件为下列内容(我有一个gitlab账号，一个github账号)：

 #default gitlab
    Host gitlab
      HostName gitlab
      PreferredAuthentications publickey
      IdentityFile ~/.ssh/id_rsa    

    Host github.com
      HostName github.com
      PreferredAuthentications publickey
      IdentityFile ~/.ssh/yomige_rsa

然后使用如下命令进行ssh测试，根据提示把主机添加到~/.ssh/known_hosts文件中，然后就正常了:

$ ssh -T [email protected]
The authenticity of host 'github.com (192.30.253.113)' can't be established.
RSA key fingerprint is SHA256:nThbg6kXUpJWGl7E1IGOCspRomTxdCARLviKw6E5SY8.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'github.com,192.30.253.113' (RSA) to the list of known hosts.
Hi yomige! You've successfully authenticated, but GitHub does not provide shell access.

内容参考：Github (SSH) via public WIFI, port 22 blocked.

参考文章：https://www.w3cmm.com/javascript/resize.html；