Caching

Enable the cache

1. Add a cache section to your configuration.

   cache mycache
      total-max-size 4
      max-object-size 10000
      max-age 240

   Directive	Description
   total-max-size	Sets the total memory the cache can consume in megabytes. The maximum value is 4095.
   max-object-size	Sets the max size in bytes for a single object; Larger objects will not be stored. It cannot be larger than half of total-max-size.
   max-age	Sets the seconds for an object to stay the cache; It can be overriden with a Cache-Control header.

2. Add an http-request cache-use and an http-response cache-store directive to a frontend or listen section to enable caching in that section. The filter line is required only when the section includes other filter lines, but otherwise can be omitted, since it is implicitly defined.

   frontend  fe_main
      bind :80
      filter cache mycache
      http-request cache-use mycache
      http-response cache-store mycache
      default_backend be_main

   Directive	Description
   http-request cache-use	Fetches the requested resource from the cache. Place an if or unless statement afterwards to include or exclude a resource from being cached.
   http-response cache-store	Saves the resource to the cache once it comes from the server.

Cache restrictions

Objects are cached only if all of the following are true:

• The size of the resource does not exceed max-object-size

• The response from the server is 200 OK

• The response does not have a Vary header

• The response does not have a Cache-Control: no-cache header