A request the general process

When a user enters www.taobao.com this URL in the browser, there will be a lot of action. First it will request DNS to resolve the domain name to the corresponding IP address, and then based on the IP address on the Internet to find the corresponding server, to the server to initiate a GET request, the server decided to return the default data resources to the user access. There is actually a complex business logic on the server side: There may be many servers in the server that specify which server to process the request, which requires a load balancer to evenly distribute all users ' requests, and whether the requested data is stored in a distributed cache or in a static file, or in a database When the data is returned to the browser, the browser parses the data to discover that there are still some static resources (such as CSS, JS, or pictures) when another HTTP request is initiated, and these requests are likely to be on the CDN, and the CDN server will process the user's request, in general a user request will involve so many operations. Every detail will affect whether the request will eventually succeed.

A request the general process