And the usual debug information I just found on https://www.nginx.com/resources/wiki/start/topics/tutorials/debugging/ that I should provide (very sorry for doing that in 3 parts, won't happen again):

#### nginx -V
nginx version: nginx/1.10.0 (Ubuntu)
built with OpenSSL 1.0.2g 1 Mar 2016
TLS SNI support enabled
configure arguments: --with-cc-opt='-g -O2 -fPIE -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2' --with-ld-opt='-Wl,-Bsymbolic-functions -fPIE -pie -Wl,-z,relro -Wl,-z,now' --prefix=/usr/share/nginx --conf-path=/etc/nginx/nginx.conf --http-log-path=/var/log/nginx/access.log --error-log-path=/var/log/nginx/error.log --lock-path=/var/lock/nginx.lock --pid-path=/run/nginx.pid --http-client-body-temp-path=/var/lib/nginx/body --http-fastcgi-temp-path=/var/lib/nginx/fastcgi --http-proxy-temp-path=/var/lib/nginx/proxy --http-scgi-temp-path=/var/lib/nginx/scgi --http-uwsgi-temp-path=/var/lib/nginx/uwsgi --with-debug --with-pcre-jit --with-ipv6 --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_addition_module --with-http_dav_module --with-http_geoip_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_image_filter_module --with-http_v2_module --with-http_sub_module --with-http_xslt_module --with-stream --with-stream_ssl_module --with-mail --with-mail_ssl_module --with-threads --add-module=/build/nginx-pzhfc2/nginx-1.10.0/debian/modules/nginx-auth-pam --add-module=/build/nginx-pzhfc2/nginx-1.10.0/debian/modules/nginx-dav-ext-module --add-module=/build/nginx-pzhfc2/nginx-1.10.0/debian/modules/nginx-echo --add-module=/build/nginx-pzhfc2/nginx-1.10.0/debian/modules/nginx-upstream-fair --add-module=/build/nginx-pzhfc2/nginx-1.10.0/debian/modules/ngx_http_substitutions_filter_module

#### cat /etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;

events {
worker_connections 768;
}

http {
sendfile on;
tcp_nopush on
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
client_max_body_size 50m;
# Avoid timeouts
send_timeout 600;
proxy_send_timeout 600;
proxy_read_timeout 600;

include /etc/nginx/mime.types;
default_type application/octet-stream;

access_log /var/log/nginx/access.log;
error_log /var/log/nginx/error.log;
log_format compression '$remote_addr - $remote_user [$time_local] '
'"$request" $status $body_bytes_sent '
'"$http_referer" "$http_user_agent" "$gzip_ratio"'
'[$upstream_addr: $request |$upstream_connect_time|$upstream_header_time|$upstream_response_time|$request_time|$bytes_sent|$pipe|$upstream_status]';

gzip on;
gzip_disable "msie6";
include /etc/nginx/conf.d/*.conf;
include /etc/nginx/sites-enabled/*;
}


#### cat sites-enabled/load-balancer

upstream apache {
server webdevw1.myorg.edu;
}

#### cat sites-enabled/dev.www.myorg.edu

server {
listen 80;
listen [::]:80;
server_name dev.www.myorg.edu;
error_log /var/log/nginx/www.myorg.edu-error.log debug;
access_log /var/log/nginx/www.myorg.edu-access.log compression;
location / {
proxy_buffers 64 128k;
proxy_buffer_size 2k;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $remote_addr;
proxy_pass http://apache;
}
}