Докер-контейнер Nginx Reverse Proxy выдает тайм-аут 504 Gateway

У меня запущено два контейнера докеров, один из них — обратный прокси-сервер jwilder nginx. Другой - портье. Я могу получить доступ к серверной части portainer, добавив порт: 9443 к URL-адресу. Но виртуальный хост и виртуальный порт, настроенные для обратного прокси-сервера nginx, похоже, не работают. Я получаю тайм-аут шлюза 504. Я использую следующие файлы docker-compose.yml, каждый со своим Dockerfile в одной папке:

Для обратного прокси nginx (compose)

version: '3.3'

services:
    nginxproxy: 
        build: .
        container_name: nginxproxy_container
        restart: always
        ports:
            - 80:80
            - 443:443
        volumes:
            - /etc/letsencrypt/live/mydomain.nl/cert.pem:/etc/nginx/certs/mydomain.nl.crt:ro
            - /etc/letsencrypt/live/mydomain.nl/privkey.pem:/etc/nginx/certs/mydomain.nl.key:ro
            - /var/run/docker.sock:/tmp/docker.sock:ro
            
networks:
  default:
    external:
      name: cloud01_network

Для обратного прокси nginx (Dockerfile)

FROM nginxproxy/nginx-proxy
EXPOSE 80
EXPOSE 443

Для портье (композитор)

version: '3.3'

volumes:
  portainer_data:
  
services:
    portainer:
        build: .
        container_name: portainer_container
        restart: always
        ports:
            - 9443:9443
            - 8000:8000
        # Environment variables
        environment:
            # Virtual host for nginx-proxy
            VIRTUAL_PROTO: https
            VIRTUAL_HOST: cloud01.mydomain.nl
            VIRTUAL_PORT: 9443
        volumes:
            - portainer_data:/data
            - /etc/letsencrypt/live/mydomain.nl:/certs/live/mydomain.nl:ro
            - /etc/letsencrypt/archive/mydomain.nl:/certs/archive/mydomain.nl:ro
            - /var/run/docker.sock:/var/run/docker.sock
        command:
            --ssl
            --sslcert /certs/live/mydomain.nl/fullchain.pem
            --sslkey /certs/live/mydomain.nl/privkey.pem
            
networks:
  default:
    external:
      name: cloud01_network

Для переносчика (Dockerfile):

FROM portainer/portainer-ce:latest
EXPOSE 9443
EXPOSE 8000

Теперь https://cloud01.mydomain.nl:9443 прекрасно запускает серверную часть portainer. Но https://cloud01.mydomain.nl не делает того, что я ожидал. Я просмотрел файл /etc/nginx/conf.d/default.conf в контейнере nginx. Который был автоматически сгенерирован следующим образом:

# nginx-proxy version : 1.0.0-4-g4ea3437
# If we receive X-Forwarded-Proto, pass it through; otherwise, pass along the
# scheme used to connect to this server
map $http_x_forwarded_proto $proxy_x_forwarded_proto {
  default $http_x_forwarded_proto;
  ''      $scheme;
}
# If we receive X-Forwarded-Port, pass it through; otherwise, pass along the
# server port the client connected to
map $http_x_forwarded_port $proxy_x_forwarded_port {
  default $http_x_forwarded_port;
  ''      $server_port;
}
# If we receive Upgrade, set Connection to "upgrade"; otherwise, delete any
# Connection header that may have been passed to this server
map $http_upgrade $proxy_connection {
  default upgrade;
  '' close;
}
# Apply fix for very long server names
server_names_hash_bucket_size 128;
# Default dhparam
ssl_dhparam /etc/nginx/dhparam/dhparam.pem;
# Set appropriate X-Forwarded-Ssl header based on $proxy_x_forwarded_proto
map $proxy_x_forwarded_proto $proxy_x_forwarded_ssl {
  default off;
  https on;
}
gzip_types text/plain text/css application/javascript application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;
log_format vhost '$host $remote_addr - $remote_user [$time_local] '
                 '"$request" $status $body_bytes_sent '
                 '"$http_referer" "$http_user_agent" '
                 '"$upstream_addr"';
access_log off;
                ssl_protocols TLSv1.2 TLSv1.3;
                ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384';
                ssl_prefer_server_ciphers off;
error_log /dev/stderr;
resolver 127.0.0.11;
# HTTP 1.1 support
proxy_http_version 1.1;
proxy_buffering off;
proxy_set_header Host $http_host;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection $proxy_connection;
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 $proxy_x_forwarded_proto;
proxy_set_header X-Forwarded-Ssl $proxy_x_forwarded_ssl;
proxy_set_header X-Forwarded-Port $proxy_x_forwarded_port;
proxy_set_header X-Original-URI $request_uri;
# Mitigate httpoxy attack (see README for details)
proxy_set_header Proxy "";
server {
        server_name _; # This is just an invalid value which will never trigger on a real hostname.
        server_tokens off;
        listen 80;
        access_log /var/log/nginx/access.log vhost;
        return 503;
}
        # cloud01.mydomain.nl
        upstream cloud01.mydomain.nl {
        ## Can be connected with "cloud01_network" network
        # portainer_container
        server 172.27.0.3:9443;
        }
server {
        server_name cloud01.mydomain.nl;
        listen 80 ;
        access_log /var/log/nginx/access.log vhost;
        # Do not HTTPS redirect Let'sEncrypt ACME challenge
        location ^~ /.well-known/acme-challenge/ {
                auth_basic off;
                auth_request off;
                allow all;
                root /usr/share/nginx/html;
                try_files $uri =404;
                break;
        }
        location / {
                return 301 https://$host$request_uri;
        }
}
server {
        server_name cloud01.mydomain.nl;
        listen 443 ssl http2 ;
        access_log /var/log/nginx/access.log vhost;
        ssl_session_timeout 5m;
        ssl_session_cache shared:SSL:50m;
        ssl_session_tickets off;
        ssl_certificate /etc/nginx/certs/mydomain.nl.crt;
        ssl_certificate_key /etc/nginx/certs/mydomain.nl.key;
        add_header Strict-Transport-Security "max-age=31536000" always;
location / {
                proxy_pass https://cloud01.mydomain.nl;
}
}

Я возился с этим уже пару дней, но не могу продвинуться дальше этого.