sh: connect to host github.com port 22: Connection refused

如果使用git远程推送时出现如下问题：

 [fulinux@ubuntu learngit]$ git push -u 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.

可以采用如下方法：

 [fulinux@ubuntu ~]$ vim .ssh/config

 Host github.com
 User [email protected]
 Hostname ssh.github.com
 PreferredAuthentications publickey
 IdentityFile ~/.ssh/id_rsa
 Port 443

测试连接是否成功：

 [fulinux@ubuntu ~]$ ssh -T [email protected]
 Hi fulinux! You've successfully authenticated, but GitHub does not provide shell access.

推送：

 [fulinux@ubuntu learngit]$ git push -u origin master
 The authenticity of host '[ssh.github.com]:443 ([192.30.252.151]:443)' can't be established.
 RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
 Are you sure you want to continue connecting (yes/no)? yes
 Warning: Permanently added '[ssh.github.com]:443,[192.30.252.151]:443' (RSA) to the list of known hosts.
 Counting objects: 23, done.
 Delta compression using up to 2 threads.
 Compressing objects: 100% (18/18), done.
 Writing objects: 100% (23/23), 1.87 KiB | 0 bytes/s, done.
 Total 23 (delta 6), reused 0 (delta 0)
 To [email protected]:fulinux/learngit.git
  * [new branch]      master -> master
 Branch master set up to track remote branch master from origin.