GCE Node.js not working in different PORT

Question

I want to deploy a node.js app with pm2 and express into a Compute Engine Instance, it works fine in port 8080, but when i change the port to 8081, it returns me "500 Internal Server Error".

I also have a firewall rule with that port.

/etc/nginx/sites-available/default:

server {
    listen 8081;
    server_name **.***.***.***;

    location / {
        proxy_pass "http://127.0.0.1:8081";
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_cache_bypass $http_upgrade;
    }
}

server {
    listen 80;
    server_name **.***.***.***;
    root /var/www/html/;
}

In my file /home/myuser/.pm2/logs/index-error.log says: "ADDRESS ALREADY IN USE"

File: /var/log/nginx/error.log:

1260 768 worker_connections are not enough while connecting to upstream

I've tried with the next command: sudo.netstat -tulpn

And the only process that uses this port is the firewall rule that I create

Answer 1

Try this Below possible Solutions:

1)Set the maximum number of simultaneous connections that can be opened by a worker process. Please go through Worker_connections for more information. Also check full example configuration .

The formula for connections is worker_processes * worker_connections which should be 12 * 768, which would be (click clack) 9216. But your logs say 1768…

events {
    worker_connections 10000;
}

Try this on your app.yml:

Any custom commands to run after building run:

• exec: echo "Beginning of custom commands"

• replace:

  filename: "/etc/nginx/nginx.conf"

  from: "worker_connections 768"

  to: "worker_connections 2000"

• replace:

  filename: "/etc/nginx/nginx.conf"

  from: "worker_processes auto"

  to: "worker_processes 10"

Be aware that your block on post 2 is acting on the wrong file!

Another way to increase the limit is by setting worker_rlimit_nofile 10000 and had no issues, you can safely increase it, though, the chance of running out of file descriptors is minuscule. Package bbb-config now sets worker_rlimit_nofile 10000 ; and worker_connections 4000 ; in /etc/nginx/nginx.conf # 11347

Note: Note to CentOS / Fedora users, if you have SELinux enabled, you will need to run setsebool -P httpd_setrlimit 1 so that nginx has permissions to set its rlimit.

2)Check you may need to use a body parser to convert data to req.body github.com/expressjs/body-parser

3)Check the problem is now a linux kernel limit, see easyengine.io/tutorials/linux/increase-open-files-limit

Please see similar SO for more information.