Why does my node app process keep getting stopped when I use forever?

Question

On a free-tier Amazon EC2 instance, I set up a simple node.js Hello World app running on express.

If I run npm start, my app runs fine and I can hit it from my browser, and I see the following output:

> [email protected] start /home/ec2-user/app
> node ./bin/www

I have installed the forever tool globally. When I run forever start app.js, I see:

warn:    --minUptime not set. Defaulting to: 1000ms
warn:    --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms
info:    Forever processing file: app/app.js

However, when I check forever list, I see that the process has stopped:

info:    Forever processes running
data:        uid  command             script forever pid  id logfile                          uptime  
data:    [0] 2v0J /usr/local/bin/node app.js 2455    2457    /home/ec2-user/.forever/2v0J.log STOPPED 

This is the only message in the log: error: Forever detected script was killed by signal: null

I'm unable to find any other log information. Why does it keep immediately stopping?

EDIT: I tried running it as nohup forever start app.js and got the same problem. I'm running the forever start and the forever list in the same ssh session, one after the other. The app's process seems to stop immediately.

Answer 1

I'm guessing the process stops after you disconnect from ssh?

Try running forever with nohup first.

nohup forever start app.js

When you disconnect from ssh the server kills all your shell's child processes. nohup disconnects a process from its parent shell.

Answer 2

I was able to resolve my problem thanks to this answer on a similar question: https://stackoverflow.com/a/24914916/1791634

The process kept running when I used forever start ./bin/www instead of passing app.js

It remains to be seen whether this causes any trouble down the road.