Add section on SSH access issues with GitHub in specific environments, including troubleshooting steps and configuration for using port 443. This addresses common connectivity problems faced in restrictive network settings.

Author: zeroDtree

content/计算机/ssh.md

@@ -7,6 +7,7 @@
   - [4. Proxy Forwarding](#4-proxy-forwarding)
   - [5. ssh via proxy](#5-ssh-via-proxy)
   - [6. proxy using ssh](#6-proxy-using-ssh)
+  - [7. 特殊环境下ssh无法访问github问题](#7-特殊环境下ssh无法访问github问题)
 
 ## 1. Basic Usage
 
@@ -103,3 +104,30 @@ Host server_ip
 ```
 ssh -D {local port} {username}@{server}
 ```
+
+## 7. 特殊环境下ssh无法访问github问题
+
+一些公司、学校实验室的防火墙，或者某些运营商，为了安全起见，会封锁 22 端口
+
+使用ssh git clone会出现以下错误
+
+```bash
+zengls188@dell-Precision-7960-Tower ~/proj> git clone git@github.com:xxx/yyy.git
+Cloning into 'yyy'...
+ssh: Could not resolve hostname github.com: Temporary failure in name resolution
+fatal: Could not read from remote repository.
+
+Please make sure you have the correct access rights
+and the repository exists.
+```
+
+解决办法：
+
+在`~/.ssh/config`中添加如下配置
+
+```
+Host github.com
+	Hostname ssh.github.com
+	Port 443
+	User git
+```