Run Node App as Linux Service

Vikram Rao on NodeJS Linux Deployment 5th June, 2021 • 10 mins

This post describes how to run a NodeJS web application as a linux service with a dedicated user to get the benefits of systemd services.

To start with

Let us call our app my-nodejs-app. The application is deployed at /usr/share/my-nodejs-app. Here we also assume the NodeJS app uses standard express app template that creates an executable entry point at bin/www in the app source. If not then some of the paths below might need to be changes as per your executable path.

Create a dedicated user for the service

It is always better to run as much as possible any process without root privileges. So let us create a dedicated user for our NodeJS app -

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useradd -r -s /bin/false my-nodejs-app-user

• This creates a user who cannot login from SSH
• It also creates corresponding group
• It does not create home directory and we don’t need this user to have one

Grant the designated user access to the app directory

This is self explanatory

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chown -R my-nodejs-app-user:my-nodejs-app-user /usr/share/my-nodejs-app

Write a systemd config file

Create a systemd config file as below at /etc/systemd/system/my-nodejs-app.service

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[Unit]
Description=my-nodejs-app

[Service]
Type=simple
ExecStart=/bin/node /usr/share/my-nodejs-app/bin/www
WorkingDirectory=/usr/share/my-nodejs-app
User=my-nodejs-app-user

# Environment variables: production|development
Environment=NODE_ENV=production

# Allow many incoming connections
LimitNOFILE=infinity

# Allow core dumps for debugging
LimitCORE=infinity

StandardInput=null
StandardOutput=journal+console
StandardError=journal+console
Restart=always

[Install]
WantedBy=multi-user.target

Start the service

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systemctl start my-nodejs-app

Verify

• Verify the process has started -

  
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  systemctl status my-nodejs-app.service
  
  

  If all is well you should see active (running) message like -

  
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  my-nodejs-app.service - my-nodejs-app
   Loaded: loaded (/etc/systemd/system/my-nodejs-app.service; enabled; vendor preset: disabled)
   Active: active (running) since Sun 2021-05-23 09:49:02 UTC; 1min 28s ago
  
  

• Check additional information about the service -

  
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  journalctl -xe -u my-nodejs-app.service
  
  

• Verify the process is running as the designated user and not root -

  
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  ps -aef --forest | grep my-nodejs-app
  
  

  The above command should show an output like this -

  
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  my-node+  1202     1  0 09:49 ?        00:00:01 /bin/node /usr/share/my-nodejs-app/bin/www
  
  

Adios…