Node-Red multiple instances, RPi

Updated 2022-07-04 !

On the same server/hardware you can have

• a test environment for Node-Red(NR), separated from production
• separated instances for different applications

Setup will follow for a Raspberry Pi(RPi) including how to auto start at power on.

A post for NR quick install.

Directory for the new instance

Here I assume that I will be running a new project called "p1", and therefore I add a new subdirectory in the Node-Red directory.  Log on to the Raspberry with terminal/ssh.

mkdir .node-red/p1

The original settings for Nod-Red is ".node-red/settings.js" and I use this as base for the new instance, with command

cp .node-red/settings.js  .node-red/p1/settings.js

Settings

You could edit the "p1" settings with 

nano .node-red/p1/settings.js

but the overrides will be done in the command.

Start the new instance

Start with 

node-red -u /home/pi/.node-red/p1/ -p 1881

Option "-u" points to the "p1" user directory, with it's settings file, and "-p" redirects to port 1881. Command line usage.

The new instance can be accessed at 

http://Your-host:1881/

The "p1" instance will be up and running as long as You stay in the ssh session. Terminate with Ctrl + c.

Another tip could be to create a file "nrp1.sh" and add a row with the command "node-red -u /home/pi/.node-red/p1/ -p 1881" and then save. Then it's easy to start the "p1" instance with just 

bash nrp1.sh

Autostart
If You want to have the "p1" instance to start at power on and restart at failure add a service file for systemd. Copy the original service file as the base for the "p1" instance with 

sudo cp /lib/systemd/system/nodered.service /lib/systemd/system/noderedp1.service

and edit it with 

sudo nano /lib/systemd/system/noderedp1.service

Change the ExecStart line to

ExecStart=/usr/bin/env node-red-pi $NODE_OPTIONS $NODE_RED_OPTIONS -u /home/pi/.node-red/p1/ -p 1881

and save. Activate the service with 

sudo systemctl daemon-reload
sudo systemctl enable noderedp1
Created symlink /etc/systemd/system/multi-user.target.wants/noderedp1.service → /lib/systemd/system/noderedp1.service.
sudo systemctl start noderedp1

Check status with 

sudo systemctl status nodered*

If You want to delete the systemd service, for the "p1" project, do 

sudo systemctl stop noderedp1
sudo systemctl disable noderedp1

and then delete the ”noderedp1.service” file.

Inspiration
Got inspiration, among others, from Steve.