Backend requires an HTTP server of varnish cache. It can process HTTP requests classified by policies, but not limited to one web server, one CMS, one Load balancer, or other varnish. Varnish does not care whether the object is HTML, XML, JPEG or ebcdic. For vanrish, they are all bytes. The client sends an HTTP request to varnish, such as a browser, search engine spider, script, and criminals. Header is an HTTP header, for example, "Accept-encoding :". Hit obtains the target from the varnish cache. One of the two master (process) varnish processes, the master process is a management program responsible for managing Configuration, parameters, and editing them, but it never comes into contact with the real HTTP stream. Miss whether a target is obtained from the backend server and put into varnish cache according to the situation. Response to a content in object cached. Varnish receives a response from the backend server and creates a target. The cached content can respond to the client. Pass varnish does not try to find the target in the cache, but simply retrieves it from the backend server. Pipe varnish only forwards requests to the backend. The request client sends varnish and varnish to the backend. The things that the response backend sends to varnish and varnish send to the client. When the response is stored in the varnish cache, we call it an object. Varnish (NB: with 'D') is the real varnish cache program. It is just a program. However, when you run it, two processes are generated, master and worker (or child ). Varnishhist eye-candy program showing responsetime histogram in 1980ies ascii-art style. varnishlog the program that displays varnish transaction processing logs in the specified format varnishncsa the program that displays varnish transaction processing logs in the NCSA format. Varnishstat varnish transaction processing counter program. Varnishtest uses the specified script to test varnish. Varnishtop specifies the time when the log is used. the VCL varnish configuration file worker (process) is being configured and started by the master process. It handles almost all the work we want varnish to handle. When it goes down, the master will try to start it to keep the website available.
