id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,uname,nginx_version 2063,nginx reports seemingly incorrect “upstream split a header line in FastCGI records”,MatTheCat@…,,"This is a follow-up of https://github.com/symfony/symfony/issues/38462 where you will be able to find a way to reproduce the problem. By enabling the debug mode I got [debug] http fastcgi parser: -2 [debug] upstream split a header line in FastCGI records [error] upstream sent too big header while reading response header from upstream before every header could be sent. Note the [error] log seems inconsistent with the previous [debug]. I believe it has something to do with stderr so I checked https://github.com/nginx/nginx/commit/593dec8b35e3997a18592e678845dedea28a57ef but I’m not able to guess what’s going on. ",defect,closed,minor,,documentation,1.19.x,invalid,,,"Linux 4e4771383dfc 5.8.14-arch1-1 #1 SMP PREEMPT Wed, 07 Oct 2020 23:59:46 +0000 x86_64 Linux","nginx version: nginx/1.19.3 built by gcc 9.3.0 (Alpine 9.3.0) built with OpenSSL 1.1.1g 21 Apr 2020 TLS SNI support enabled configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid --lock-path=/var/run/nginx.lock --http-client-body-temp-path=/var/cache/nginx/client_temp --http-proxy-temp-path=/var/cache/nginx/proxy_temp --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp --http-scgi-temp-path=/var/cache/nginx/scgi_temp --with-perl_modules_path=/usr/lib/perl5/vendor_perl --user=nginx --group=nginx --with-compat --with-file-aio --with-threads --with-http_addition_module --with-http_auth_request_module --with-http_dav_module --with-http_flv_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_mp4_module --with-http_random_index_module --with-http_realip_module --with-http_secure_link_module --with-http_slice_module --with-http_ssl_module --with-http_stub_status_module --with-http_sub_module --with-http_v2_module --with-mail --with-mail_ssl_module --with-stream --with-stream_realip_module --with-stream_ssl_module --with-stream_ssl_preread_module --with-cc-opt='-Os -fomit-frame-pointer' --with-ld-opt=-Wl,--as-needed"