This describes how to run node-red and the MQTT server on Android, using Termux.


An Android device with an internet connection. I used a Moto G2 running stock Android 6.0

Install Termux

Termux is an app that provides a Linux environment running on Android. Install from the Play Store. When opened it should provide a terminal interface to the Linux system.

See for how to enter Ctrl chars etc. In particular Ctrl-C is Vol Down+C and Up arrow is Vol Up+W

Allow Termux to access the device filesystem [optional]

I found it useful to allow Termux to access the Android filesystem, so that it became easy to move files between the device and the PC by plugging it into the PC USB. To do this, in Termux, run


This setups up a folder storage in termux which is a symlink to /storage/emulated/0. Run

ls -al storage

to see what is there. For example storage/downloads is the Download folder.

Install an editor

You will need an editor for editing configuration files and such like. nano is the simplest. To install it using the Termux package manager, which is a wrapper round apt, run

pkg install nano

If you prefer another editor then install that instead.

Install ssh server [optional]

If you are like me then as soon as possible you will want to install the ssh server in Termux so that you can connect to the Linux system from your PC so you don’t have to laboriously enter terminal commands using the touch screen. Install the ssh server.

pkg install openssh

The ssh server only allows connection using keys rather than a username/password so you need the public key from your client (the PC). This will likely be in the .ssh folder on the PC and will be called If you haven’t got a public key then you can generate this on the PC using

ssh-keygen -t rsa

This needs to be copied to the Android device. This can be done by connecting it to the PC using a USB cable then using the file manager on the PC to move the file into the Download folder on the device. Alternatively it could be picked up directly from the PC using scp on the device. The key then needs to be added to the authorized_keys file on the device which can be done using

cat storage/downloads/ >> .ssh/authorized_keys

Now start the ssh server on the device using


To connect to the device using ssh it needs to be accessible on the local network and you need to know its IP address. In termux run


Look for the section starting wlan0 (assuming you have connected via wifi) and in that section you should see something like


which is the IP address. I like to allocate a fixed IP address so that the device always has the same address but I am not going to cover that here.

To connect from the PC you also need an ssh client. On Linux this is likely to be ssh. On Windows you will may have to use something like PuTTY. Here I will assume that ssh is the command. So on the PC run

ssh -p 8022 <IP>

Where <IP> is the IP address, so for example

ssh -p 8022

and you should be connected.

Start ssh server automatically

The server can be started automatically be creating a file called .profile and putting in there

# start ssh daemon if not already running
#if ! pgrep sshd >/dev/null 2>&1; then
#    sshd

That file will be executed when Termux is opened and will start the server provided it is not already running.

Most of the following can now be run on the PC connected to the device.

Install Mosquitto

pkg install mosquitto

Create a configuration file for mosquitto

cd ~
mkdir .mosquitto
nano .mosquitto/mosquitto.conf

and put in there

persistence true
autosave_interval 300
persistence_location /data/data/com.termux/files/home/.mosquitto/		(note, trailing / is mandatory)
log_dest file /data/data/com.termux/files/home/.mosquitto/mosquitto.log

If you don’t want to use retained topics then you don’t need the first three lines.

Mosquitto is then started using

mosquitto -c /data/data/com.termux/files/home/.mosquitto/mosquitto.conf -d

which will start it in the background, with the log going to .mosquitto/mosquitto.log

Running the command

tail -f .mosquitto/mosquitto.log

will show that file in the terminal, and will show new entries as they appear, which can be useful if all is not working as expected. To get more verbose logging add -v to the mosquitto command line.

Start mosquitto automatically

As for the ssh server, mosquitto can be started automatically be adding to the file .profile

# start mosquitto in daemon mode provided not already running
if ! pgrep mosquitto >/dev/null 2>&1; then
    mosquitto -c /data/data/com.termux/files/home/.mosquitto/mosquitto.conf -d