Configuring Gitlab and NGINX

I am trying to set up an existing NGINX to work with Gitlab omnibus on CentOS. I currently have another app installed (App A) that uses 127.0.0.1:3838. As long as I have NGINX setup so that by going to my site IP 12.345.678.910 I can redirect Application A. I would like to configure Gitlab so that when I go to 12.345.678.910/gitlab it redirects me to Gitlab. The idea is to start Gitlab at http://127.0.0.1:8081 and redirect NGINX 12.345.678.910/gitlab to localhost: 8081.

I followed these links for help:

https://docs.gitlab.com/omnibus/settings/nginx.html#using-a-non-bundled-web-server .

Redirect to GitLab subdomain with existing Nginx installation

Edited / etc / gitlab / gitlab.rb

external_url = 'http://127.0.0.1:8081'
nginx['enable'] = false
web_server['external_users'] = ['nginx']

      

        
        
        
      

    

New config file / etc / nginx / sites -enabled / gitlab

upstream gitlab-workhorse {
    server unix:/var/opt/gitlab/gitlab-workhorse/socket;
}

server {
  listen 0.0.0.0:8081;
  listen [::]:8081;
  server_name localhost;
  server_tokens off;
  root /opt/gitlab/embedded/service/gitlab-rails/public;

  access_log  /var/log/nginx/gitlab_access.log;
  error_log   /var/log/nginx/gitlab_error.log;

location / {
  client_max_body_size 0;
  gzip off;

  proxy_read_timeout      300;
  proxy_connect_timeout   300;
  proxy_redirect          off;
  proxy_http_version 1.1;
  proxy_set_header    Host                $http_host;
  proxy_set_header    X-Real-IP           $remote_addr;
  proxy_set_header    X-Forwarded-For     $proxy_add_x_forwarded_for;
  proxy_set_header    X-Forwarded-Proto   $scheme;
  proxy_pass http://gitlab-workhorse;
 }
}

      

        
        
        
      

    

Added to /etc/nginx/conf.d/default.conf:

server {
    listen 80 default_server;
    server_name localhost;
location / {
    root /usr/share/nginx/html;
    index index.html index.htm;
}
location /gitlab {
    proxy_pass http://127.0.0.1:8081;
}

      

        
        
        
      

    

I added "nginx" to the gitlab-www group. Run nginx restart and gitlab reconfigure commands.

sudo usermod -aG gitlab-www nginx
sudo service nginx restart
sudo gitlab-ctl reconfigure && gitlab-ctl restart

      

        
        
        
      

    

I installed Passenger per comment in the link above, but that didn't fix the problem. So when I go to 12.345.678.910/gitlab I get a page not found error.

I am still new to all of this and any help would be appreciated.