Just for the sake of completeness, it should be fairly straightforward to write a plugin or even use conf_remap/header_rewrite to basically strip Cache-Control headers from the Origin AND override proxy.config.http.negative_caching_enabled to false on a 400 status from the Origin.
Although, my reading of your original question was to modify the default ATS behaviour to *never* cache 400s (and that you clearly already knew it can be done via a plugin). - Sudheer > On Nov 9, 2016, at 1:59 PM, Alan Carroll > <solidwallofc...@yahoo-inc.com.INVALID> wrote: > > Yes, it's about proxy.config.http.negative_caching_enabled. My reading of the > document is that > 1) If enabled, the negative response is cached regardless of any > Cache-Control: value.2) If disabled, the negative response is cached only if > origin provide Cache-Control indicates it should be. > > >
