Node.js+Nginx 抛出 502 bad gateway 错误答案

【问题标题】：Node.js+Nginx throwing 502 bad gateway errorNode.js+Nginx 抛出 502 bad gateway 错误
【发布时间】：2018-11-12 09:58:34
【问题描述】：

我刚刚将 Node.js 应用程序安装到开发环境。配置是： Ubuntu 16.x PHP 7.0 节点.js 8.x mysql PhpMyAdmin Nginx

我的节点应用程序使用端口 2000，子文件夹名称是 nodeapp。虽然 phpmyadmin 正常打开，但 Node 应用程序给出 502 Bad gateway。

这里是 nginx 配置文件：

server {
    listen 80 default_server;
    listen [::]:80 default_server;
        listen 2000;

    root /home/pjsp/public_html;
    index index.php index.html index.htm index.nginx-debian.html app.js;

    server_name mydomain.com;

    location /nodeapp {
    proxy_pass http://localhost/nodeapp:2000;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
}
    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php7.0-fpm.sock;
    }

    location ~ /\.ht {
        deny all;
    }

}

以下是我在 /var/log/nginx/error.log 文件中遇到的错误：

2018/06/02 13:13:15 [error] 32209#32209: *763 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 127.0.0.1, server: mydomain.com, request: "GET /nodeapp:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000

请帮忙！

更新：

新建配置文件：

server {
    listen 80 default_server;
    listen [::]:80 default_server;
        #listen 2000;

    root /home/pjsp/public_html;
    index index.php index.html index.htm index.nginx-debian.html app.js;

    server_name app.pajasa.com www.app.pajasa.com;

    location /nodeapp {
    proxy_pass http://localhost;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
}
    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php7.0-fpm.sock;
    }

    location ~ /\.ht {
        deny all;
    }

}

现在出现错误：

2018/06/02 14:52:35 [alert] 3026#3026: *765 768 worker_connections are not enough while connecting to upstream, client: 127.0.0.1, server: app.pajasa.com, request: "GET /nodeapp:2000 HTTP/1.1", upstream: "http://127.0.0.1:80/nodeapp:2000", host: "www.app.pajasa.com"

网址：www.app.pajasa.com/nodeapp:2000

【问题讨论】：

标签： node.js nginx ubuntu-16.04

【解决方案1】：

你的 nginx 中有一个无限循环。这就是你看到的原因：

/nodeapp:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000:2000....

如果您的 Node 应用正在侦听端口 2000，请不要在 Nnginx 上使用 listen 2000;。

在你放弃之后，请求：http://localhost/nodeapp 将被传递到你的节点应用程序。

另外，你的proxy_pass不正确，应该是：

 proxy_pass http://localhost:2000;

更新

您的网址错误

www.app.pajasa.com/nodeapp:2000 // INCORRECT

首先正如我们已经提到的，如果你使用 Nginx 代理到你的 Node.js APP，你不必在 URL 上添加端口，其次更重要的是这不是端口工作：

www.app.pajasa.com:2000 // This is correct

从 URL 中删除 :2000，Nginx 会将其代理到您的节点应用程序。

www.app.pajasa.com/nodeapp

【讨论】：

谢谢，我按照你的建议改了，现在日志错误改如下： 2018/06/02 13:32:46 [alert] 2367#2367: *2293 768 worker_connections are not enough while连接到上游，客户端：127.0.0.1，服务器：app.pajasa.com，请求：“GET /nodeapp:2000 HTTP/1.1”，上游：“127.0.0.1:80/nodeapp:2000”，主机：“www.app.pajasa.com”
谢谢 .. 现在也一样，错误是：[error] 2476#2476: *1 connect() failed (111: Connection refused) while connection to upstream, client: 175.100.142.211, server ：app.pajasa.com，请求：“GET /nodeapp:2000 HTTP/1.1”，上游：“127.0.0.1:2000/nodeapp:2000”，主机：“www.app.pajasa.com”
抱歉，您没有正确执行此操作，您请求：/nodeapp:2000，这是无效的。只需请求：http://localhost/nodeapp 你在任何地方都不需要 2000，Nginx 会为你处理端口转发，这就是使用 nginx 的全部意义
现在错误是：3026#3026: *765 768 worker_connections 连接上游时不够用，客户端：127.0.0.1，服务器：app.pajasa.com，请求：“GET /nodeapp:2000 HTTP/1.1”，上游：“127.0.0.1:80/nodeapp:2000”，主机：“www.app.pajasa.com”
你的节点服务器在运行吗？再次发布完整的 nginx 配置，并确保您的应用正在运行：curl http://localhost:2000 它输出什么？

【解决方案2】：

proxy_pass http://localhost:2000/nodeapp;

你的 URL 方案是错误的，它总是 PROTO://DOMAIN:PORT/PATH

【讨论】：

CHanged ，但现在出现以下错误：[alert] 2367#2367: *2293 768 worker_connections 连接上游时不够用，客户端：127.0.0.1，服务器：app.pajasa.com，请求：“GET /nodeapp:2000 HTTP/1.1”，上游：“127.0.0.1:80/nodeapp:2000”，主机：“www.app.pajasa.com”

【解决方案3】：

    listen 2000;

你的 nginx 不应该监听应用端口。在这种情况下，nginx 会递归调用它。

【讨论】：

谢谢，我对此发表了评论，并将代理通行证更改为 proxy_pass localhost/nodeapp;现在错误正在对此进行更改：[alert] 2367#2367: *2293 768 worker_connections 在连接到上游时不够用，客户端：127.0.0.1，服务器：app.pajasa.com，请求：“GET /nodeapp:2000 HTTP /1.1”，上游：“127.0.0.1:80/nodeapp:2000”，主机：“www.app.pajasa.com”