Simple way to ping node js app and automatically restart pm2 proccess - node.js

We have linux ubuntu 20 server with pm2 and nginx. And two node js app running via pm2. Is there any simple way to monitor some app endpoint and automatically restart pm2 app if this endpoint is not responding? I know about PM2 monitor - but it costs 40 USD for month. Maybe there is another way to configure it?

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Node express server always shuts down

I have a angular app running in a universal express server.
I start the server with
nohup node server.js &
exit
The server runs fine, but after a while 5 to 30 Minutes it stops with nothing in the nohup logs.
Same happens with forever or pm2, after a while the server is gone without any hint for the error.
Any ideas how to debug, this is on a hosting environment.
Thanks

Node js deployement in Azure server could not be accesses outside using ip

I tried deploying a simple node js service in azure ubuntu using CLI,console logs says the server is up on port 8080(this same service works perfectly in my local machine),but when i tried to access the public ip from outside,it gives site can't be reached
Following was the output when i deployed my service
azureuser#myVM:~/drugdemo/user_service/drulistService$ vi server.js
azureuser#myVM:~/drugdemo/user_service/drulistService$ node server.js
App is listening on 8080
^C^C
azureuser#myVM:~/drugdemo/user_service/drulistService$ pm2 start server.js
[PM2] Starting
/home/azureuser/drugdemo/user_service/drulistService/server.js in fork_mode (1 instance)
[PM2] Done.
Use `pm2 show <id|name>` to get more details about an app
azureuser#myVM:~/drugdemo/user_service/drulistService$
Please help me with your suggections.
(I already tried changing 'localhost' to '0.0.0.0' and '127.0.0.1' but didn't work for me)
Thank you in advance
Make sure to open the firewall port via Azure as well and not just the server.
This may help: https://blogs.msdn.microsoft.com/pkirchner/2016/02/02/allow-incoming-web-traffic-to-web-server-in-azure-vm/

App not starting with pm2 after stopping execution

I have an app set to listen to port 66.
First I tried to run it with sudo node myapp.js . I was able to access it at the correct url (ip:66). Then I stopped the app (Ctrl+c) and started it with pm2, sudo pm2 start app.js. The status is online. However, that same url is now inaccessible.
Running sudo pm2 logs while the app is started with pm2 gives me the error EACCESS for port 66. No one else is running the app, and I am sure I am only using one console and killing the node service before starting it with pm2.
Pm2 was installed globally. Server is Debian stretch. Nodejs version is 8.x
I am logging as a normal user and using sudo to run the app.
on linux systems normal users are not allowed to listen to ports below 1024. There are several ways around this.
You can change this rule to allow non root users to open such ports. But this is a security risc and is not recommended. So i won't add a link to this solution.
you can also listen to a port that is greater than 1024 and then use a forward rule in your firewall to route port 66 to the port you opened.
https://www.systutorials.com/816/port-forwarding-using-iptables/
my (and pm2's) prefered solution is to listen to a port greater than 1024 and use a reverse proxy like nginx to route apps running on that server.
http://pm2.keymetrics.io/docs/tutorials/pm2-nginx-production-setup

My Express Node.JS App times out

I have installed Node.js on my web server plus the dependencies for Express. When I run the command npm start and go to my web site's address using the port 3000 (which I believe the app is set to by default?), it just keeps loading and never loads. Any tipps please on how to fix this?
Try this $ PORT=8080 node app.js. Here app.js is your server config file. I suspect some background servers are running in that port 3000.

nginx service won't start after reboot AWS Linux server

A few weeks ago I configured an ec2 server on AWS and database is on RDS and I use nginx as web server. When i reboot server from the AWS console my nginx wont restart automatically. I did this using service nginx start command.
Is there any way to configure nginx server, So it restarted when i reboot my ec2 instance
You may configure nginx to start automatically on system boot using below command.
#chkconfig nginx on
Once you run above command, nginx will be always started whenever system boots.
You may check , if service is configured to start automaticaly on system boot using below command.
# chkconfig nginx --list
You may disable service auto start using below command
# chkconfig nginx off

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