Question

502 error when running Node app with PM2

Posted March 19, 2020 133

Nginx Node.js

I have followed the instructions laid out in this tutorial https://www.digitalocean.com/community/tutorials/how-to-set-up-a-node-js-application-for-production-on-ubuntu-18-04.

I can successfully run my application using

$ sudo node app.js

and access it in my browser.

However, when I run the app using

$ pm2 start app.js

it says the app is running but when I access it in the browser I get a 502 Bad Gateway error. Any ideas?

By:

digitaloceanjd

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

×

1 answer

bobbyiliev March 19, 2020

Hi there @digitaloceanjd,

It sounds like that the application might not be starting, what happens if you try to get information for your application with:

pm2 info app_name

And also try to use the pm2 monit command to check the status of the application.

I would also recommend checking your Nginx error logs:

tail -100 /var/log/nginx/error.log

Another thing that I could suggest is making sure that your application is listening on the correct port:

sudo netstat -plant

Let me know how it goes!
REgards,
Bobby

Reply Report

digitaloceanjd March 19, 2020
Hi Bobby, thanks for your response!

running $ pm2 status says that the app is online.

running $ tail -100 /var/log/nginx/error.log shows this error:

(111: Connection refused) while connecting to upstream, client: 76.10.141.38, server: <example>.com, request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:9000/", host: "<example>.com"

so it seems to be a permissions issue with pm2 - any ideas?

Thanks,
Joseph
Reply Report
- bobbyiliev March 20, 2020
  
  Hi there @digitaloceanjd,
  
  Thanks for sharing the extra details!
  
  I would recommend running a netstat to make sure that your backend application is actually listening on port 9000. To do that you can run the following command:
  
  netstat -plant
  
  Feel free to share the output here.
  
  Also, another thing that you could share is the exact Nginx server block that you are using.
  
  Regards,
  Bobby
  
  Reply Report

Submit an Answer

Looking for something else?

Ask a new question Search for more help