id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
826	Add config option for NGX_HTTP_CACHE_VARY_LEN	Neil Craig		"Hi

Currently NGX_HTTP_CACHE_VARY_LEN is hardcoded at 42 characters in length. This is undocumented and causes us major issues (as we vary on zero to many header values) in our reverse proxy setup.

I have a workaround currently which is a build-time patch (against 1.9.x):
https://gist.github.com/neilstuartcraig/62cb5236eeabab9a8a4d

It would be really nice if this could be a configurable option to make it simple to change without mandating users compile nginx from source.

I have had messages via comments and twitter since documenting this on my blog (https://thedotproduct.org/nginx-vary-header-handling/) from several people who hit the same issue.

Cheers
Neil"	enhancement	closed	minor		nginx-core	1.9.x	fixed	vary header		n/a	n/a