git 报错 ssh:connect to host github.com port 22

kex_exchange_identification: Connection closed by remote host
Connection closed by 140.82.121.3 port 22
fatal: Could not read from remote repository.

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

 突然发现git无法操作，报错如上图。

本来以为是ssh key失效了？检查了一下是对应的。

测试

$ ssh -T  [email protected]

结果依然是 

上网找方法：

测试端口443 ，是可以成功的 

$ ssh -T -p 443 [email protected]

参考网上方法，解决办法如下：

 找到git 的config文件  /etc/ssh/ssh_config 并编辑

$ vi /etc/ssh/ssh_config    

没有权限的话用sudo

在末尾添加下面代码并保存

Host github.com
User git
Hostname ssh.github.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa
Port 443

成功！ 

接下来就可以正常操作git啦！