Multisite with Nginx and AWS

[Aviran_Katz]

Hi everyone,
I’m trying to transform a single site to a multisite.
The server tech is nginx, and the whole system is containerized.
There are two docker containers: a container for the bedrock and a different container for nginx.
We also use ELB for load balancing.
I tried adding the following lines with no success, in application.php and default.conf:

application.php:

define( 'WP_ALLOW_MULTISITE', true );
define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', true);
define('DOMAIN_CURRENT_SITE', 'http://localhost');
define('PATH_CURRENT_SITE', '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

default.conf:

server {
	listen 80;

	index index.php;

	location / {
		try_files $uri $uri/ /index.php?$args;
		proxy_read_timeout 150;

	}

	location ~ \.php$ {
		try_files $uri =404;
		fastcgi_split_path_info ^(.+\.php)(/.+)$;
		include fastcgi_params;

		...
	}

	# Prevent PHP scripts from being executed inside the uploads folder.
	location ~* /app/uploads/.*.php$ {
		deny all;
	}


	location ~* ^.+\.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|rss|atom|jpg|jpeg|gif|png|ico||bz2|doc|xls|ppt|mid|midi|wav|bmp|rtf)$ {
        ...
	}

	# This should match upload_max_filesize in php.ini

	#upload files size restriction
	location ~* ^.+\.(jpg|jpeg|gif) {
		client_max_body_size 6m;
	}

	location ~* \.(avi|mp4) {
		client_max_body_size 15m;
	}

	# Deny public access to wp-config.php
	location ~* wp-config.php {
		deny all;
	}

	# nginx block xmlrpc.php requests
	location /xmlrpc.php {
		deny all;
	}

	#articles
	location ~ ^/[\d+]/articles/(.*) {
	#   rewrite_log on;
		return 301 https://$host/?p=$1;
	}

	location ~ ^/[\d+]/item/(.*) {
	#   rewrite_log on;
		return 301 https://$host/?p=$1;
	}

	client_max_body_size 6m;

	rewrite ^/(wp-.*.php)$ /wp/$1 last;
	rewrite ^/(wp-(content|admin|includes).*) /wp/$1 last;

}

When I navigate to https://mysite.com/wp/wp-admin/network.php I receive the message:

Warning: An existing WordPress network was detected.

I cannot configure the network or add content to any site in it. It’s if it didn’t exist.
What am I missing here?