nginx配置dns-Go服务器开发

在Nginx中配置DNS解析有多种方式，以下是常见的配置方法：

1. 使用变量实现动态DNS解析

http {
    resolver 8.8.8.8 114.114.114.114 valid=30s;
    
    server {
        listen 80;
        server_name example.com;
        
        location / {
            set $backend "backend.example.com";
            proxy_pass http://$backend:8080;
            proxy_set_header Host $host;
        }
    }
}

2. upstream块中的DNS配置

http {
    resolver 8.8.8.8 114.114.114.114 valid=30s;
    
    upstream backend_servers {
        zone backend_zone 64k;
        server backend1.example.com:8080 resolve;
        server backend2.example.com:8080 resolve;
    }
    
    server {
        listen 80;
        
        location / {
            proxy_pass http://backend_servers;
            proxy_set_header Host $host;
        }
    }
}

3. 详细的resolver配置

http {
    # DNS解析器配置
    resolver 8.8.8.8 114.114.114.114 valid=30s ipv6=off; 
    
    # resolver参数说明:
    # valid=30s - DNS记录缓存时间
    # ipv6=off - 禁用IPv6解析
    # status_zone - 状态监控区域
    
    upstream dynamic_backend {
        server api.example.com service=http resolve; 
    }
}

4. stream模块中的DNS配置（TCP/UDP代理）

stream {
    resolver 8.8.8.8 valid=30s;
    
    upstream database_cluster {
        zone database_zone 64k;
        server db1.example.com:3306 resolve; 
        server db2.example.com:3306 resolve; 
    }
    
    server {
        listen 3306;
        proxy_pass database_cluster; 
     } 
}

5 . 完整示例：带健康检查的动态代理

http {  
     resolver     127 .0 .0 .11  8 .  88 .  44 valid=60s;  
     
     upstream web_services {  
         zone       web_pool  64k ;   
         server     service1 .example .com :  80 resolve ;   
         server     service2 .example .com :  80 resolve ;   
     }  

     server {  
         listen      80 ;   
         server_name localhost ;   

         location /health {  
             access_log off ;   
             return     200 "healthy \n" ;   
         }  

         location / {  
             proxy_pass          http : //web_services ;
             proxy_set_header      Host              $host ;
             proxy_set_header      X-Real-IP         $remote_addr ;
             proxy_set_header      X-Forwarded-For   $proxy_add_x_forwarded_for ;
             
             # DNS解析失败处理
             proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504;  
             proxy_next_upstream_tries 2;  
             proxy_next_upstream_timeout 3s;  
          }  
      }  
}

6 . Docker环境中的特殊配置

http {  
     # Docker内部DNS服务器 (CoreDNS/dockerd内置DNS)   
     resolver      127 .0 .0 .11 valid=10s ipv6 = off ;   

     upstream container_apps {       
          server app1 :8080 resolve ;       
          server app2 :8080 resolve ;       
     }

     ...其他配置...
}

关键注意事项：

1️⃣ resolver必须配置：使用变量或resolve时必须有resolver指令

2️⃣ 缓存时间valid：根据业务需求设置合理的DNS缓存时间

3️⃣ 多DNS服务器：建议配置多个DNS服务器提高可靠性

4️⃣ 容器环境：Docker中使用127.0.0.11作为DNS服务器

5️⃣ IPv6控制：如不需要IPv6，使用ipv6=off禁用

内容由零声教学AI助手提供，问题来源于学员提问