nginx.conf

user  nginx;
worker_processes  1;
error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;
events {                     
    worker_connections  1024;
}
http {
    client_max_body_size 0;
    upstream docker-nginx {
        least_conn;
        server boostore_blue:3000;
        server boostore_green:3000;
    }
    server {
        listen 80;
        server_name localhost;
        location / {
            proxy_pass         http://docker-nginx;
            proxy_redirect     off;
            proxy_set_header   Host $host;
            proxy_set_header   X-Real-IP $remote_addr;
            proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;          
        }
    }
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';
    access_log  /var/log/nginx/access.log  main;
                                                
    sendfile        on;                                                                         
    keepalive_timeout  65;                                                                      
    include /etc/nginx/conf.d/*.conf;           
}