Duplicate Location "/" Nginx Error Backend And Frontend - node.js

Question

I'm running an Express server on port 5000 and a React app on 8080.
My idea was to just direct traffic based on location (uri), but I've been getting a duplicate location "/" error with this partial insert into the AWS Beanstalk ngnix config:
location / {
root /var/app/current/build/;
try_files $uri /index.html;
proxy_http_version 1.1;
proxy_pass http://127.0.0.1:8080/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header Connection $connection_upgrade;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
location /socket-io {
proxy_pass http://127.0.0.1:5000/;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-NginX-Proxy true;
proxy_set_header X-Real-IP $remote_addr;
proxy_ssl_session_reuse off;
proxy_cache_bypass $http_upgrade;
}
This gets included in a standard ngnix.conf which looks roughly like this: https://gist.github.com/alextanhongpin/00da7f551969f052e57f3c4dcd9ac4b0

Answer 1

This is some combination of this answer and this other one since AWS documentation keeps changing.
On EC2, the file /etc/nginx/conf.d/elasticbeanstalk/00_application.conf is the file that appears to get appended on the main nginx.conf file with the line /etc/nginx/nginx.conf.
HOWEVER
The latest documentation says having .platform/nginx/conf.d/your_custom.conf in your working directory is the real nginx extension file.
I had to manually change 00_application.conf on EC2 in order for the duplicate error to go away, it appears this file stayed default even when redeploying with the custom config files, and that file happens to have a location / {}.
So I would recommend the container_command method or manually changing it for now.