我在研究数字海洋水滴。
https://docs.strapi.io/developer-docs/latest/setup-deployment-guides/deployment/optional-software/nginx-proxy.html#strapi-server
我已经尝试按照这个指南几个小时了，但我就是不能让它工作。当我试图连接，我得到502坏网关，不知道这意味着什么。当我只是8011端口启用通过防火墙和连接到端口直接通过DNS，它工作正常。
做nginx -t说语法没问题，我试过很多次重启服务，键都能用。
/etc/nginx/conf.d/upstream.conf：

# Strapi server
upstream strapi {
  server 127.0.0.1:8011;
}

etc/nginx/sites-available/default：

server {
        # Listen HTTP
        listen 80;
        server_name losslessly-api.djkato.net;

        # Redirect HTTP to HTTPS
        return 301 https://$host$request_uri;
}

server {
        # SSL configuration
        #
        listen 443 ssl;
        listen [::]:443 ssl;

        ssl_certificate     /etc/nginx/certificate/losslessly-api.djkato.net.crt;
        ssl_certificate_key /etc/nginx/certificate/losslessly-api.djkato.net.key;

        server_name losslessly-api.djkato.net;

        # Proxy Config
        location / {
        proxy_pass http://strapi;
        proxy_http_version 1.1;
        proxy_set_header X-Forwarded-Host $host;
        proxy_set_header X-Forwarded-Server $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_set_header Host $http_host;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_pass_request_headers on;
    }
}

./config/server.js：

module.exports = ({ env }) => ({
  host: env('HOST', '0.0.0.0'),
  port: env.int('PORT', 8011),
  url: 'https://losslessly-api.djkato.net',
});

sudo ufw status：

Status: active

To                         Action      From
--                         ------      ----
OpenSSH                    ALLOW       Anywhere
8011/tcp                   DENY        Anywhere
Nginx HTTP                 ALLOW       Anywhere
Nginx HTTPS                ALLOW       Anywhere
8011                       DENY        Anywhere
Nginx Full                 ALLOW       Anywhere
OpenSSH (v6)               ALLOW       Anywhere (v6)
8011/tcp (v6)              DENY        Anywhere (v6)
Nginx HTTP (v6)            ALLOW       Anywhere (v6)
Nginx HTTPS (v6)           ALLOW       Anywhere (v6)
8011 (v6)                  DENY        Anywhere (v6)
Nginx Full (v6)            ALLOW       Anywhere (v6)