using sudo with ExecStart (systemd)

Question

I am trying to get a node.js site live on port 80 (I am using Digital Ocean). I doing this using systemd with in service file

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ExecStart=/usr/bin/nodejs /var/www/bin/app.js
...

On localhost this works fine on port 80 if I use sudo to start the site, but not without sudo. Apparently you need to run as root for ports below 1024.

How do I allow sudo in the ExecStart? Or am I going completely the wrong way here and if so, how do I get the express app on port 80?

Cheers, Mike

Answer 1

Systemd starts the executable stated in ExecStart= as root by default.

However, if you have specified User= or Group= in your service file overriding that default, and still need to run an executable that requires sudo, prepend the command with the absolute path to your sudo location:

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ExecStart=/usr/bin/sudo /usr/bin/nodejs /var/www/bin/app.js
...

Answer 2

Systemd starts the executable stated in ExecStart= as root by default. This means if you haven't specified User= or Group= in our service file, your binary is started privileged.

You can verify this by starting id, or whoami program. Ex: ExecStart=/usr/bin/id or ExecStart=/usr/bin/whoami (note the path for the programs might be different for you)