Synchronizing, saving, and sharing data, emails, and contacts under our control based on open-source software? Securely accessing our home network from everywhere in the world based on the most modern Virtual private Network technology? With just a Raspberry Pi? Yes, we want it! Today we will install NextCloud and Wireguard on our Raspberry Pi and make it work together.
You will save a lot of time using the tricks presented in the next few minutes. And we will use IOTstack.

First we have to install Raspberry OS on an SSD and udate it as usual.
Next we install IOTstack with this command:

git clone https://github.com/SensorsIot/IOTstack.git IOTstack
cd IOTstack

Now we install Docker using the menu of IOTstack

./menu.sh

Next create compose-override.yml and copy-paste the content from Google drive: https://drive.google.com/file/d/1ja5Gzzwhkfz2IMq4nHFjsefGJe4nGBTj/view?usp=sharing

nano compose-override.yml

This file will be merged every time you start menu.sh. So make sure to restart menu.sh every time you change this compose-override.yml.

Customize Wireguard

•Add a domain in duckDNS

Go to https://www.duckdns.org/ and create a domain.
Next we have to add the token and the domain in file duck.sh

nano ~/IOTstack/duck/duck.sh

Next we have to schedule a task to call DuckDNS

crontab -e

Add this line at the bottom of the file:
*/5 * * * * sudo ~/IOTstack/duck/duck.sh >/dev/null 2>&1

Now you have to foreward port 51820 for UDP:

Now you can test the script to make sure it works
sudo ~/IOTstack/duck/duck.sh then cat /var/log/duck.log. If you get KO then something has gone wrong and you should check out your settings in the script.

Add url to compose-override.yml

nano compose-override.yml

Decide how many “tunnels” you need and adjust the “PEERS” parameter.
If you build now a stack using menu.sh with at least Wireguard ticked your Wireguard server should run.

Add Wireguard client on Smartphone or PC

Now you can install the Smartphone app on Android or IOS and to create a tunnel for each device.
Display the respective .png file in directory :~/IOTstack/services/wireguard/config/peerXXX and add a tunnel with your Smartphone camera.

If you switch your tunnel on, you should be connected to your home network.

Install NextCloud

We have to change the passwords in compose-override.yaml. You can leave them for a test. They have to match as in the example below.

nano compose-override.yml

Now we can build the final docker-compose.yml file using

./menu.sh

tick at least Portainer-CE (the new community edition of Portainer), MariaDB, Nextcloud, and Wireguard. Of course you can select additional containers if needed.
If we start docker again, also nextCloud should run on the server and we can configure it using the browser. NexCloud answers on port 9321:

Becasue we use the recommended MariaDB we have to enter the names and credentials:

The password comes from MYSQL_PASSWORD in compose-override.yml

Add a data disk to NextCloud

You have to add this line to override-compose.yml

and mount a disk. I use gparted on the Raspberry desktop to format a disk using ext4.

Next mount the disk by creating a directory:

mkdir /Disk1

Now you have to find out the PARTUUID of your new disk:

sudo blkid

And add a line into fstab

sudo nano /etc/fstab
PARTUUID=dab6f534-01 dev/Disk1           ext4    defaults,auto,users,rw,nofail 0 0

Now the disk should be mounted after the next reboot. Just add the owner and the permissions:

sudo chown -R www-data:www-data /Disk1
sudo chmod -R 0750 /Disk1

And you should be ready to go

Start your Stack

Now you can re-run the ./menu.sh and start docker.

./menu.sh
docker-compose -f docker-compose.yml up -d

If you go to port 9002 of your Raspberry you should see Portainer.

A remotely controlled, precise analog wall clock like that one from IKEA is a cool thing. Today we will build our own remote control for such analog and digital clocks. All we need is a Raspberry Pi and a few electronic components. And we will learn something about resonance frequencies, capacitors, and ferrite antennas. Let’s hack!

This is material presented in the following video:

Installation:

Source of the software: https://github.com/hzeller/txtempus

sudo apt-get install git build-essential -y
git clone https://github.com/hzeller/txtempus.git
cd txtempus
make

Start command:

sudo ./txtempus -v -s DCF77

Options:
        -s <service>          : Service; one of 'DCF77', 'WWVB', 'JJY40', 'JJY60', 'MSF'
        -r <minutes>          : Run for limited number of minutes. (default: no limit)
        -t 'YYYY-MM-DD HH:MM' : Transmit the given local time (default: now)
        -z <minutes>          : Transmit the time offset from local (default: 0 minutes)
        -v                    : Verbose.
        -n                    : Dryrun, only showing modulation envelope.
        -h                    : This help.

Automatic Startup:

Create a service file for systemd:

Create a service file: 
sudo nano /lib/systemd/system/remoteClock.service

Insert the following content:

[Unit]
  Description=My Sample Service
  After=multi-user.target

[Service]
 Type=idle
 ExecStart=/home/pi/txtempus/txtempus -v -s DCF77 > /home/pi/remoteClock.log 2>&1 

[Install]
  WantedBy=multi-user.target 

Press ctrl-X , Y and Enter to save the file

Set the permission:

sudo chmod 644 /lib/systemd/system/remoteClock.service

Restart systemd

sudo systemctl daemon-reload
sudo systemctl enable remoteClock.service

sudo reboot 

Safe Shutdown

This is material presented in this video:

If you pull the plug on a Raspberry Pi during operation, it is well possible that it will never boot up again, because its SD card is corrupted. This is what we will change today. And I will show you a few other useful tricks you might not find right away.

Only connecting the switch is not enough. We have change the config.txt file using this command:

sudo nano /boot/config.txt

and add the following line to the file:

dtoverlay=gpio-shutdown,gpio_pin=3,active_low=1,gpio_pull=up

ctrl-X and Yes and, after a reboot, it should work.

Increase Swap File

The next trick concerns installations with high memory consumptions, mainly on the Pi Zero. I learned it when I used Node-Red, influxDB, and Grafana on a Pi Zero. After a while, the device blocked and had to be rebooted. Using the reboot switch from before, BTW.

The “top” command revealed the problem: No more Swap space available. This means that Linux does not get enough resources and blocks. Swap space is used by the operating system if the main memory is not big enough. Then, it stores less needed content to the “slow” SD card. Of course, this happens earlier the smaller your RAM is.

The Pi zero only has 512 MB RAM, and the operating system assigns 102MB swap space. The Pi 3 has 1 GB RAM, and the operating system assigns the same amount. For the Pi 3 this is not as critical because it needs much less of this space. What to do?

We enter the command:

 sudo nano /etc/dphys-swapfile 

and then uncomment the line:

CONF_SWAPFILE=/var/swap and CONF_SWAPFACTOR=2

This creates a swapfile which has 2 times the size of RAM, which seams to be best practice.

And we have to comment the line CONF_SWAPSIZE=100

Ctrl-Z , Y, and enter.

Then we have to invoke these two commands:

sudo dphys-swapfile setup

and

sudo dphys-swapfile swapon

After reboot, we see that the swap file is much bigger and, also after a time, Raspbian will still have free swap space. The Pi zero does not become a racing car with this change. But at least it does not block.

Wi-Fi Setup without Keyboard and display (headless)

We want to connect a “fresh” Raspberry to a Wi-Fi network first time without display and keyboard.

If you create a new SD image and boot your Pi, it cannot connect to your Wi-Fi network because it does not know the credentials and therefore you cannot connect to it to change the SSID or the password. The old “Henn” and “egg” problem.
Here is the trick: after writing the image to the SD card, you can remove and insert it gagain into the reader. You will get an error message. Just ignore it. Now you see this picture . We need to add two files. One is called:

” wpa_supplicant.conf” and the other ssh without an extension.

“wpa_supplicant.conf” has to contain the following lines:

The first is your country, and here you have to enter the Wi-Fi credentials. Save it to the SD card.

country=CH
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
network={
ssid=”…..”
psk=”…..“
}

The file with the name ssh can be empty. It just has to be there. Usually I create a blank text file and remove the extension.

Now we can boot a Raspberry with this SD card, and it will connect to Wi-Fi and enable SSH. As needed. My tip: I store a wpa_supplicant.conf file on my PC which includes my credentials. Then I just have to copy it to the new SD card.

This is supporting material for the following videos:

Install RTL_SDR Support

cd ~

sudo apt-get install git git-core cmake libusb-1.0-0-dev
build-essential

git clone git://git.osmocom.org/rtl-sdr.git

cd rtl-sdr/ && mkdir build && cd build/

cmake ../ -DINSTALL_UDEV_RULES=ON

sudo make

sudo make install

sudo ldconfig

cd ~

sudo cp ./rtl-sdr/rtl-sdr.rules /etc/udev/rules.d/

sudo reboot

# create file no-rtl.conf

sudo nano /etc/modprobe.d/no-rtl.conf

# add these three lines

blacklist dvb_usb_rtl28xxu
blacklist rtl2832
blacklist rtl2830

sudo reboot

lsusb

rtl_test -t

Build and install rtl_433

sudo apt-get install libtool libusb-1.0.0-dev librtlsdr-dev
rtl-sdr doxygen

git clone https://github.com/merbanan/rtl_433.git

cd rtl_433/ && mkdir build &&
cd build && cmake ../ &&
make

sudo make install

Test installation:

rtl_433

The source for this tutorial is: https://sdr-setup-notes.readthedocs.io/en/latest/dev_rtlsdr.html#rtl-433-tool-setup

Install supervisord

sudo apt-get install -y supervisor

sudo nano /etc/supervisor/conf.d/rtl_433.conf

Enter into file:

[program:rtl_433]
command=/home/pi/rtl_433/build/src/rtl_433 -R 123 -F “mqtt://localhost:1883,,user=”admin”,pass=”admin”,events=BEER”user=pi
autostart=yes
autorestart=yes
startretries=100
stderr_logfile=/var/log/rtl_433/rtl_433.err.log
stdout_logfile=/var/log/rtl_433/rtl_433.log

sudo mkdir /var/log/rtl_433

sudo service supervisor start

sudo service supervisor status

If you changed the configuration file:

sudo supervisorctl reread

You are done!

Raspberry Pis are very good for monitoring all sorts of things. Today we will use Node-Red, InfluxDB, and Grafana for monitoring as well as enable Smartphone and Mail alarming.

Passwords

Prepare Image on SD card

Download image: http://bit.ly/2GdZbPe
Add empty ssh file to root directory of the card
Add wpa_supplicant.conf to root directory

Content of wpa_supplicant.conf file:

country=CH
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
network={
  ssid=”…”
  psk=”…”
}

Insert SD card into your Raspberry, boot, and find its IP address using https://www.advanced-ip-scanner.com
Log-in using Putty https://www.putty.org/
update your Raspberry to the newest version:

 sudo apt-get update && sudo apt-get upgrade 

Configuration on the Raspberry

Configuration of Mosquitto

sudo nano /etc/mosquitto/mosquitto.conf 

insert:
allow_anonymous true

Restart Mosquitto

 sudo systemctl restart mosquitto 

Configuration of influxDB

Create User:

CREATE USER "pi" WITH PASSWORD 'raspberry' WITH ALL PRIVILEGES

exit

Change config file:

sudo nano /etc/influxdb/influxdb.conf

In [http] uncomment:
enabled = true and bind-address=:8086

in [monitor] uncomment and change to:
store-enabled = false

sudo service influxdb restart

Configuration of Node-Red

Import Flows from: https://drive.google.com/open?id=1kECuykSaFO7Qb_67QqIHtlpvElpVWDMI

Install Mail

sudo apt-get install ssmtp
sudo apt-get install mailutils

sudo nano /etc/ssmtp/ssmtp.conf

For Gmail enter this text:

mailhub=smtp.gmail.com:587
AuthUser=[yourmailaddress]@gmail.com
AuthPass=[emailPassword]
UseSTARTTLS=YES
UseTLS=YES

Test your Mail

echo "Hello world email body" | mail -s "Test
Subject" sensorsiot@gmail.com

Add support for less secure apps in Gmail: https://myaccount.google.com/lesssecureapps

Create influxDB database

influx

Create database [your databaseName]
Show DATABASES
Use [your databaseName]
Show series

exit

Install and prepare Telegram

Install Telegram on your PC https://desktop.telegram.org/

Start telegram and search for “botfather”

Enter the name of your desired bot. Note down the token.
Send a text message to the bot.

Go to: https://api.telegram.org/bot[Token]/getUpdates

and take a note of the ID. We will use it later:

Prepare Grafana

Examples:
Beer Pressure: https://drive.google.com/open?id=1beKyu4WuGErAHeYKyE3-8wtpyZJ8yHkZ
Weather: https://drive.google.com/open?id=18326_tjcVln0xBLRJINJn2ZwP0lNlyHX
YouTube: https://drive.google.com/open?id=1TrZAGnxn4zRfyO_X8RXw4ZtQIvJi8JnQ

Add Mail Notification Channel

sudo nano /etc/grafana/grafana.ini

enabled=true
host = smtp.gmail.com:587
user =[receivingEmail]@gmail.com
password =”[emailPassword]”
skip_verify = true
from_address = [sendingEmail]@gmail.com
from_name = [whateverName]

And press “Send Text”

Add Telegram Notification Channel

Insert chatID and token from before

And press “Send Test”

You are done!