Unable to run node app using systemd - node.js

Question

This going to be my first node deployment. I have this app which runs fine on my Debian 9 server using this command:
cd /srv/myapp && NODE_ENV=production yarn start
And print out this message:
yarn run v1.6.0
$ babel-node index.js
In order to demonize the app using systemd, I created `/lib/systemd/system/myapp.service:
[Unit]
Description=Myapp
[Service]
ExecStart=/home/john/start.sh
Type=simple
User=john
Restart=on-failure
[Install]
WantedBy=multi-user.target
and in start.sh I have:
cd /srv/myapp && NODE_ENV=production yarn start
Hoewever, when I run systemctl start myapp the node app does not start to listen on port 3000, as expected (netstat -tulpn | grep :3000
returns no results)
# systemctl status myapp
● myapp.service - Myapp
Loaded: loaded (/lib/systemd/system/myapp.service; disabled; vendor preset: enabled
Active: failed (Result: exit-code) since Sun 2018-05-13 06:14:04 EDT; 5s ago
Process: 8852 ExecStart=/home/bob/start.sh (code=exited, status=203/EXEC)
Main PID: 8852 (code=exited, status=203/EXEC)
May 13 06:14:04 9606 systemd[1]: myapp.service: Unit entered failed state.
May 13 06:14:04 9606 systemd[1]: myapp.service: Failed with result 'exit-code'.
May 13 06:14:04 9606 systemd[1]: myapp.service: Service hold-off time over, scheduling
May 13 06:14:04 9606 systemd[1]: Stopped myapp.
May 13 06:14:04 9606 systemd[1]: myapp.service: Start request repeated too quickly.
May 13 06:14:04 9606 systemd[1]: Failed to start myapp.
May 13 06:14:04 9606 systemd[1]: myapp.service: Unit entered failed state.
May 13 06:14:04 9606 systemd[1]: myapp.service: Failed with result 'exit-code'.
I have other variations on myapp.service but could not manage to run node.
What could be wrong here? How can I fix it?

Answer 1

Process: 8852 ExecStart=/home/bob/start.sh (code=exited, status=203/EXEC)
According to systemd.exec(5), this means systemd could not execute the specified file:
203 EXIT_EXEC The actual process execution failed (specifically, the execve(2) system call). Most likely this is caused by a missing or non-accessible executable file.
You should check if /home/bob/start.sh is executable and has correct shebang specified (that is, the first line of your script must be #!/bin/bash).