Http基础

1.什么是静态资源，有什么作用和优缺点.

URL固定，后缀名一般是html，htm

优点：性能高，体验好，维护起来比较难

2.什么事动态资源，有什么作用和优缺点。

有数据库支持，后缀名是php，jsp，do，sap，aspx等

优点：交互性好（注册，登录）  维护简单

缺点：因为需要解析，所哟性能差  URL变化不利于搜索

 

3.什么是伪静态，作用及优缺点

动态URL伪装成静态，rewrite规则模块

优点：利于SEO（网站推广）

缺点：会有一点影响网站性能，因为要重写URL

 

4.什么是URL，URI，MIME

 

5.什么是Http状态码，不同的状态码分别是什么意思。

200 - OK，服务器成功返回网页 
    - Standard response for successful HTTP requests.

301 - Moved Permanently（永久跳转），请求的网页已永久跳转到新位置。
    - This and all future requests should be directed to the given.

403 - Forbidden（禁止访问）,服务器拒绝请求
    - forbidden request (matches a deny filter) => HTTP 403
    - The request was a legal request, but the server is refusing to respond to it.

404 - Not Found,服务器找不到请求的页面。
    - The requested resource could not be found but may be available again in the future.

500 - Internal Server Error（内部服务器错误）
    - internal error in haproxy => HTTP 500
    - A generic error message, given when no more specific message is suitable.

502 - Bad Gateway（坏的网关）,一般是网关服务器请求后端服务时，后端服务没有按照http协议正确返回结果。
    - the server returned an invalid or incomplete response => HTTP 502
    - The server was acting as a gateway or proxy and received an invalid response from the upstream server.

503 - Service Unavailable（服务当前不可用）,可能因为超载或停机维护。
    - no server was available to handle the request => HTTP 503
    - The server is currently unavailable (because it is overloaded or down for maintenance).

504 - Gateway Timeout（网关超时）,一般是网关服务器请求后端服务时，后端服务没有在特定的时间内完成服务。
    - the server failed to reply in time => HTTP 504
    - The server was acting as a gateway or proxy and did not receive a timely response from the upstream server.

　　　　状态码转自：http://oldboy.blog.51cto.com/2561410/716294