id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
872	allow to switch off disabled renegotiation proxy to  SSL client certificate protected backends	WolfgangFahl@…		"https://www.ruby-forum.com/topic/6875137

describes the scenario. A backend SSL Client Certificate secured server needs renegotiation.

Nginx fails 1.8.x fails badly on this with my Ubuntu 14.04.3 LTS
after having successfully solved the riddle in http://serverfault.com/questions/622855/nginx-proxy-to-back-end-with-ssl-client-certificate-authentication/746816#746816

The workaround to reconfigure the backend Apache Server is more than ugly. The worst part is the major effort needed to find out this problem in the first place - at lease nginx should mention that it actively forced the problem. curl/wget/openssl all run with no problem just nginx behaves this badly. "	enhancement	closed	minor		documentation	1.8.x	fixed			Linux nebo 3.13.0-71-generic #114-Ubuntu SMP Tue Dec 1 02:35:20 UTC 2015 i686 i686 i686 GNU/Linux	nginx version: nginx/1.8.0