当我使用nginx代理服务时，为什么localhost和localhost之间有这么多的tcp连接

Question

当我使用nginx代理服务时，为什么localhost和localhost之间有这么多tcp连接。 这是我的nginx代理配置：

server {
    listen 80;
    server_name www.domain1.com;
    location /{
    proxy_pass http://localhost:4999;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection keep-alive;
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
    }
}
 server {
    listen 80;
    server_name www.domain2.com;
    location /{
    proxy_pass http://localhost:4999;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection keep-alive;
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
    proxy_connect_timeout 300s;
    proxy_send_timeout 300s;
    proxy_read_timeout 300s;
    }
  }

Answer 1

Nginx在这里充当反向代理，为一个http请求建立客户端代理tcp连接和代理服务器tcp连接（http keep-alive将重用tcp conn）

我猜在配置proxy_pass http://localhost:4999;的客户端关闭客户端代理后，代理服务器连接将被关闭

您可以尝试以下配置：

upstream backend {
   server localhost:4999;
   keepalive 10;
}

server {
   listen 80;
   server_name www.domain2.com;
   location /{
      proxy_pass http://backend;
   }
}