Installing Node Red
Node-Red is a node application and before you Install node red you will need to first install node. Here are the instructions:
Then you can Install node red on Windows and Linux (including raspberry pi) using:
npm install -g --unsafe-perm node-red
Using the -g option add node-red command to your path. See the documentation.for more details.
Starting Node Red
To start node red on Windows go to a command prompt and type:
node c:\node\node_modules\node–red\red.js
Note: you may need to change into the node directory.
You should also be able to use the simple:
node-red
if you installed node-red using the -g option.
On Linux:
Firstly running node by typing node may not work as apparently node is a shortcut to nodejs and the shortcut may not be present.
In addition there appears to be a naming conflict with another package. see this explanation
The screen shot show how to create the symbolic link
Now that node is working you can run node-red.
Type node-red at the command prompt
. If that doesn’t work it’s probably because the link isn’t configured as shown above. You can try the alternative.
nodejs /usr/local/bin/node-red
As shown below
At the top of the screen you can see the version of node and node-red that you are using and the location of the flows..
At the bottom of the screen it tells you the url to use to access the node-red web interface which you use to create your flows.
This console stays open and you will find it useful as when you start creating flows you will see log information appearing there.
Starting Node-Red as a Service
You can also start node-red using:
node-red-start
which starts node-red as daemon.
to stop it use:
node-red-stop
Starting Node-Red on Boot
You can automatically start node-red on system start by using the command:
sudo systemctl enable nodered.service
and disable it using:
sudo systemctl disable nodered.service
When running on startup you can stop it using the node-red-stop command and restart using node-red-start command.
If you want to load node-red on startup with a different settings file than the settings.js you will need to edit the file /lib/systemd/system/nodered.service.
un-comment the line ExecStart if not already done and the Environment=”NODE_RED_OTPIONS=-v” line to something like:
Environment="NODE_RED_OPTIONS=-s /home/pi/.node-red/mysettings.js"
then reboot.
Node-Red Start Process
When node-red starts it first loads the settings file settings.js which is used to set the admin port, user directory, and flows file etc. The start process is illustrated below.
Node_Red Settings
Node red uses a settings file called settings.js. On Linux it is located in the /usr/lib/node-modules/node-red/ folder by default. on Windows it is located in c:\node-install-directory\node-modules\node-red\ .
You can create your own settings file and customise it either by copying the existing file or using the file available from Github here. To use your own settings file use the -s switch when starting node-red e.g.
node-red -s mysettingsfile.js
Important -If you place a settings.js in the .node-red folder then that will be used by default.
The documentation here takes your through the settings file in detail.
The .node-red Folder
On both Windows and Linux user settings and flows are stored in the .node-red folder. This folder is located in the users home folder.
E.G For user steve on windows and on Linux
c:\users\steve\.node-red ——–Windows
and
/home/steve/.node-red ……….. Linux
Other Command line Options
Node red has a very limited number of command line options. Use:
node-red -h
The -v switch turns on verbose mode.
The -p switch will let you change the port that node-red admin interface uses.
You can use this option to quickly and easily run multiple instances of node-red.
Running Multiple node-red instances
It is possible to run multiple node-red instances on a single machine.
To do that you will need to give each instance a different admin port and also a different user directory or alternatively create and use a new settings file.
You can do this using the -p and -u switches when starting node-red e.g
node-red -p 1881 -u user1
the admin port is 1881 and the use directory is user1 the flow file name uses the default flow name.
Note: If you don’t use a different user directory then they will all use the same flows file which could result in conflicts.
If you create a new settings file e,g mysettings.js you can then edit the line starting with flows and remove the two forward slashes.
// flowFile: my’flows.json’,
You could also change the port by editing the line near the top of the file
uiPort: process.env.PORT || 1880,
to
uiPort: process.env.PORT || 1888,
To use port 1888
You then use the command:
node-red -s mysettings.js
to start the flow.
You could also use the command
node-red -s mysettings.js -p 1889
to use a different port.
========>How to use the Admin Interface, nodes and flow basics.
Related Tutorials and resources:







Hi,
I found your page hope you can help me. I have a synology nas and installed the node-red. My problem is only run it from console, and when close the console the node red is turning off too. For me what you write:
“Starting Node-Red as a Service
You can also start node-red using:
node-red-start
which starts node-red as daemon.”
not working, because the console show this: node-red-start: command not found
I found another page can start it with pm2 https://www.rs-online.com/designspark/installing-node-red-on-a-synology-nas but it isn’t working too. 🙁 After install pm2 the console show me the same message pm2: command not found. How can I run in the background the node-red? Please help!
Try using PM2.The instructions are here
https://nodered.org/docs/getting-started/running