InfluxDB Backup Database (2 methods)

It makes sense to periodically backup InfluxDB to an external drive in-case of corruption of onboard memory. I am using a USB memory stick.

A simple cronjob can take care of this (every night 2am), open Crontab:

sudo crontab -e

and insert the below line: (change for your storage device)

0 2 * * * influxd backup -portable /media/usb/drive

Backup names start with the date it was generated but it can get messy after a few weeks.

Long term its better to run a backup script to put backups in individual directories and catch errors etc., create a python file for this and use the below example:

nano /home/pi/influx_scripts/
import os
from datetime import date

today =

d1 = today.strftime("%Y_%m_%d")
print("Date", d1)

command = "mkdir /media/usb-backup/" + d1

command = "influxd backup -portable /media/usb-backup/" + d1

command = "kapacitor backup /media/usb-backup/"+d1+"/kapacitor.db"
os.system("echo Backups Done!")
sudo crontab -e
0 2 * * * python /home/pi/influx_scripts/

You can keep an eye on the USB memory stick size by the below snip of script which can be logged to InfluxDB. A Grafana alarm keeps an eye on the size and alerts if getting close to capacity.

if [ -d "$DIRECTORY" ]; then
    usb_mem_usage=$(du -s $DIRECTORY | awk 'NR==1{print $1}')
echo $usb_mem_usage

All done!

Setup HTTPS for Grafana

By default Grafana operates over HTTP but for added security you can operate over HTTPS. For my use case I am using a self generated certificate as not using a public domain.

Generate Keys: (a key.pem and files will be generated)

openssl req -newkey rsa:2048 -new -nodes -x509 -days 3650 -keyout key.pem -out cert.pem

Put the keys in /home/pi/ directory. It did not work for me in the /etc/grafana/ directory.

sudo mv cert.pem /home/pi/
sudo mv key.pem /home/pi/

Change permissions of the keys:

sudo chmod -R 777 /home/pi/cert.pem
sudo chmod -R 777 /home/pi/key.pem 

Edit Grafana Config File:

sudo nano /etc/grafana/grafana.ini

Ensure the server protocol is updated and the key locations listed:

# Protocol (http, https, socket)
protocol = https

# https certs & key file
cert_file = /home/pi/cert.pem
cert_key = /home/pi/key.pem

Reboot system and all done!

Capacitive Touch Hack (for Fluval Edge Aquarium Control)

This post is about automating the light on the Fluval Edge Aquarium but can be applied to any capacitive touch button I imagine. It turns the light on at 10am in the morning, turns it blue at 8pm and finally turns it off at midnight. It has real time clock (RTC) to keep track of time and can recover from power outages due to storing current state in EEPROM.

My first attempt was to have passive control by creating capacitance on a piece of aluminium foil/tape and manipulating this to activate the sensor but I could not get it working so the not so elegant solution is to have a servo ‘touch’ the sensor on a schedule.

Video of it in action:

Parts Required:
Arduino (any), I used Nano.
RTC (any), I used DS1307.
Servo (any), I used HK15178 10g servo.

Connections: (aside from power which are all 5V)
Arduino A4 -> RTC SDA
Arduino A5 -> RTC SCL
Arduino D3 -> Servo Control (was yellow wire for me)

Paste of Arduino code below, don’t forget to add the RTC library, hosted here if you don’t have it already.

#include <Wire.h>
#include "RTClib.h"
#include <EEPROM.h>
#include <Servo.h>

Servo myservo;  // create servo object to control a servo 


char receivedChar;
boolean newData = false;
int pos_standby = 180;    // variable to store the servo position 
int pos_active = 100;
int led = 13;
int mode = 1;             //1 for PROD, 2 for DEV (Serial Input
int bulb_status = 0;
int starttime = 0;
int endtime = 0;
int loopcount = 0;
int address = 12;
byte value;

void setup() { 
  if (! RTC.isrunning()) {
    Serial.println("RTC is NOT running!");
  read_eeprom();              // Gets current position from EEPROM
  myservo.attach(3);          // Attaches the servo on pin 3 to the servo object 
  myservo.write(pos_standby); // Puts servo in default position
  Serial.println("Setup Complete");

  //#### Uncomment the below to set the RTC to the date & time this sketch was compiled ###
  //#### Then comment it out again and reupload sketch to Arduino ###  
  //RTC.adjust(DateTime(__DATE__, __TIME__));

void loop() {
  while (true){
      if (mode == 1) {
      starttime = millis();
      endtime = starttime;
      while (((endtime - starttime) <=10000) || (loopcount < 10000)) // do this loop for up to 10000mS
        loopcount = loopcount+1;
        endtime = millis();

    if (receivedChar=='a') {
    Serial.println("A Selected");
    servo_move(1); //Bulb ON
    else if (receivedChar=='b') {
    Serial.println("B Selected");
    servo_move(2); //Bulb BLUE
    else if (receivedChar=='c') {
    Serial.println("C Selected");
    servo_move(3); //Bulb OFF

void recvOneChar() {
 if (Serial.available() > 0) {
 receivedChar =;
 newData = true;

void showNewData() {
 if (newData == true) {
 //Serial.print("This just in ... ");
 newData = false;

void bulb_sequence() {
      DateTime now =;
      if (now.hour() > 10 && now.hour() < 20 && bulb_status!=1) {
          servo_move(1); //Bulb ON
      else if (now.hour() > 19 && now.hour() < 23 && bulb_status!=2) {
          servo_move(2); //Bulb BLUE
      else if (now.hour()>=23 && bulb_status!=3) {
          servo_move(3); //Bulb OFF

void servo_move(int x) 
  while (bulb_status != x) {

void servo() 
  myservo.write(pos_active);              // tell servo to go to position in variable 'pos' 
  delay(1000);                     // waits 1s for the servo to reach the position                       
  myservo.write(pos_standby);              // tell servo to go to position in variable 'pos' 
  delay(1000);                     // waits 1s for the servo to reach the position  
  bulb_status += 1;
  if (bulb_status == 4) {
    bulb_status = 1;
    digitalWrite(led, HIGH);  
  digitalWrite(led, LOW);  

void print_time() {
    DateTime now =; 
    Serial.print(now.year(), DEC);
    Serial.print(now.month(), DEC);
    Serial.print(, DEC);
    Serial.print(' ');
    Serial.print(now.hour(), DEC);
    Serial.print(now.minute(), DEC);
    Serial.print(now.second(), DEC);

void read_eeprom()
  // read a byte from the current address of the EEPROM
  value =;
  Serial.print("EERPROM Stored Value at Address: "); 
  Serial.print(value, DEC);
  bulb_status = value;

void write_eeprom()
  EEPROM.write(address, bulb_status);
  Serial.print("New EEPROM: ");

That’s it!

Using Python to get IP Address updates via Email

For those with Internet providers that change external IP regularly, this is a simple Python script to email you when a change occurs.

Get started by logging into your Linux Box / Raspberry Pi and install dependencies:

sudo apt-get install python-setuptools
cd /home/pi
mkdir ip_check
cd ip_check
cd requests-master/
python install

Copy the file (or copy below) into the /home/pi/ip_check directory: (Change the SMTP SETTINGS for your email address)

#!/usr/bin/env python

#This script establishes the public IP Address.
#It compares the IP to the stored IP address,
#if they differ the new IP is archived and an 
#email sent with the new IP address.

import sys
import csv
import time
import os
from smtplib import SMTP_SSL as SMTP    #This invokes the secure SMTP protocol (port 465, uses SSL)
from email.MIMEText import MIMEText     #For email
from requests import get		#Only additional package required

### Debug ###
debug = 0		#Give verbose output
force_email = 0		#Forces write to file & Email even if IP address not changed


### Program Variables ###
text_subtype = 'plain'
subject="New IP Address"
file_location = '/home/pi/ip_check/ip.csv'
archived_ip = ""
current_ip = ""

# Initialise the system and start the main loop
def main():
	check_file_exists() 	#Ensures we have a file to write to.
	get_archived_ip()	#Gets the last recorded IP Address	
	get_current_ip()	#Gets the current IP Address

def check_file_exists():
	if not os.path.isfile(file_location):
			print "File doesn't exist so creating it"
        		with open(file_location, 'a') as csvfile:
            			logfile = csv.writer(csvfile, delimiter=',')
            			logfile.writerow(["Date", "Time", "Public IP"])
			print "File Created, Updated and Email Sent"

			print "Issue writing to file"

def get_archived_ip():
	global archived_ip
	with open(file_location, 'rb') as csvfile:
		logfile = csv.reader(csvfile, delimiter=',')
		for row in logfile:
			archived_ip = row[2]
		if debug == 1:
			print 'My archived public IP address is:', archived_ip

def get_current_ip():
	global current_ip
	current_ip = get('').text

	if debug == 1:
		print 'My public IP address is:', current_ip

def compare_ip():
	if str(archived_ip) != str(current_ip) and (len(current_ip) < 100 ):
		if debug == 1:
			print "IP Address has changed"		
		if debug == 1:
			print "IP Address has not changed"	

def update_ip_file():
        	with open(file_location, 'a') as csvfile:
            		logfile = csv.writer(csvfile, delimiter=',')
			logfile.writerow([(time.strftime("%d/%m/%Y")), (time.strftime("%H:%M:%S")), current_ip])

def send_email():
	print "About to send email"
		content = "Current IP: " + str(current_ip)
		msg = MIMEText(content, text_subtype)
                msg['Subject'] = "New IP address!"
                msg['From'] = sender #some SMTP servers will do this automatically, not all.
		if debug == 1:
			print msg.as_string()

                conn = SMTP(SMTPserver)
                conn.login(USERNAME, PASSWORD)

                        conn.sendmail(sender, destination, msg.as_string())
                        print "Email Sent"                      
        except Exception, exc:
                sys.exit( "mail failed; %s" % str(exc) ) #give a error message

if __name__ == "__main__":

Okay we are now going to run it for the first time:

cd /home/pi/ip_check

All should work, not lets make it run every 15minutes automatically by cron:

crontab -e

and add the below to the file:

*/15 * * * * /usr/bin/python /home/pi/ip_check/

That’s it.

Simple Data Backup with rsync

I struggled for years to manage simple home data backups effectively but a nice Linux tool (rsync) exists to make it very manageable, here are some use cases I use frequently to make it a breeze:

A straight copy of one drive to another:

  • n – this will show the output without doing anything (dry run), remove this to run the backup.
  • r – this means recursive, basically it will catch all files.
  • u – this skips files that are newer on ‘drive2’, I use this to ensure files are a true copy in case of a mix-up.
  • v – makes the output verbose, gives lots of information on progress.
rsync -nruv /media/drive1/ /media/drive2

As of recent I started using the –checksum argument due to not following my own rules and doing a backup that overwrote modification time of all files, this argument looks at the file checksum (unique identifier) as opposed to the modification time to do a backup:

rsync -nruv --checksum /media/drive1/ /media/drive2

This was supposed to just get you on your feet with backups, a lot more options are available, read on here perhaps:

By modifying a tutorial on the opensource blog I was really able to streamline and speed up the backups, save the below as a shell script, it makes light work of multiple Terabytes of data:


for DIR in $DIRS; do
     cd "$SRC"/$DIRS
     rsync -cdlptgov --delete . /"$DEST"/$DIR
     find . -maxdepth 1 -type d -not -name "." -exec rsync -crlptgov --delete {} /"$DEST"/$DIR \;

Resources I used:

That’s it!

Easy Media Management with exiftool

I struggled for years to manage pictures effectively but a nice Linux tool (exiftool) exists to make it very manageable, here are some use cases I use frequently:

Change all times of all pictures in directory by one hour:
(change number/sign for any other hours, it is clever and will adjust day if crosses midnight etc.)

$ exiftool -AllDates+=1 -overwrite_original *

Remove all EXIF metadata from images with “.jpeg” extensions only:

exiftool -all= *.jpeg

Add if statements to operations if required: (for example only adjust picture taken with Canon Cameras)

$ exiftool -AllDates+=1 -overwrite_original -if '$make eq "Canon"' -r *

Some other rename commands that help with naming if required:

Cuts start of filename: (by 4 letters, adjust as required) (-n = dry run)

$ rename -n -v  's/^(.{4})//' *

Changes file extensions from upper case to lower case.

rename 'y/A-Z/a-z/' *.JPG

That’s it for now!

Flight Tracking on RPi Zero. (Updated to include ADSB Exchange)

Originally I ‘built my own’ FlightRadar24 node using their straightforward tutorial. Its cool and you get free premium membership on their mobile app but a lot of flights are censored which is silly as I can read them directly off my node but FR24 won’t let me see them on the app. So I ended up doing a fresh install and now I feed FR24 and also ADSB Exchange which don’t censor any flights and have some awesome local interfaces, see below for tutorial:

Start with a fresh Raspbian install on RPI. Then we install:

sudo apt-get install dump1090-fa
sudo apt-get install piaware #Not 100% sure if this line required
sudo bash -c "$(wget -O -"

The FR24 setup should guide you through first setup if its your first time, other wise you can reconfigure if you have your existing FR24 key:

sudo fr24feed --reconfigure --fr24key=your_key

I restarted the service, not sure if necessary, everything should be feeding FR24 now.

sudo systemctl restart fr24feed

See if service is running:


You can also see status if you go the FR24 local web GUI at http://192.168.1.XXX:8754/

Next we setup feed to ADSB Exchange:

sudo bash -c "$(wget -nv -O -"

It should also guide you through first setup, very straight forward, when finished you can check if service running:

sudo systemctl status adsbexchange-feed

You can see if your data is getting to ADSB Exchange by going to and you can view the global aggregated data at

There are a few other fantastic packages to install to see current stats of your system:

Tar1090 is an amazing package that shows you what your node is currently seeing, install below and then use web interface at http://192.168.1.XXX/tar1090/

sudo bash -c "$(wget -q -O -"

Timelapse1090 shows historical flights and you can replay flights etc, works well but data only stored in RAM so lost over reboot, my next plan is to write this to a database (now done). (viewable at: http://192.168.1.XXX/timelapse/)

sudo bash -c "$(wget -q -O -"

Graphs1090 is supposed to show you performance of your node, number of aircraft seen etc., didn’t get it working yet but works well for others: (viewable at: http://192.168.1.XXX/graphs1090/)

sudo bash -c "$(wget -q -O -"

You can also see the data stream from your node by the below CLI command:

nc localhost 30003

As an FYI below you can see the screenshots of the FR24 app showing the performance of my node a week after I set it up:

RPi Network CCTV Stream

I used motioneyeos for a number of years on Raspberry Pi’s (as both a Fast Network Camera and a NVR on separate devices) and while it was helpful for live viewing, the RPI really struggled on the recording frame rate.

I have since invested in a professional NVR but since I had the RPI’s lying around I decided to set them up to stream on my network and let them be captured by my new NVR or any other device that I want.

Start with a fresh install on the RPI and run the below commands:

#enable the camera if not done so already
sudo apt-get install ntpdate
sudo apt-get install vlc

Create a file on the Desktop called as per the below:

raspivid -o - -t 0 -w 1296 -h 972 -fps 8 -b 2500000 -rot 180 -a 12 | cvlc -vvv stream:///dev/stdin --sout '#rtp{access=udp,sdp=rtsp://:8554/stream}' :demux=h264

Make the file execturable:

chmod +x

Test the script by running it manually:


Making the script run on startup by creating the file:

sudo nano /etc/systemd/system/stream-rtsp.service
Description=auto start stream



Set the service to auto start:

sudo systemctl enable stream-rtsp.service

Reboot the system and confirm the system started the service by:

sudo systemctl start stream-rtsp.service

Now lets check if the device is successfully streaming by on a different device launching VLC and navigating to Media –> Open Network Stream, enter the below (modify for your IP address) and click play:


You should now see your camera screen. I will show you how to add this to Hikvision NVR in a later post.

XKCD Widget for RPi

Get your daily dose of XKCD with this python based random comic widget. Designed to run on Raspberry Pi Official 7″ LCD (800×480) but easily adapted to other screens and other picture sources if you wish.

Get the latest Python file from my GitHub:

Open up the terminal, install python packages and create a directory to keep things neat and put the github file into it:

sudo apt-get install python-bs4
sudo apt-get install python-imaging python-pil.imagetk
cd /home/pi/
mkdir code
#Copy the file into this directory/folder from GitHub.

Test the file:

python /code/

Great, all should work, lets create a Desktop shortcut:

cd /home/pi/Desktop/
nano xkcd.desktop

To make the shortcut work paste in the below code to this file and Ctrl + x to exit.

[Desktop Entry]
Name=XKCD Widget
Comment=For Official RPI LCD.
Exec=python /home/pi/Desktop/code/

Give the shortcut executable permissions:

chmod +x xkcd.desktop 

Double click on the desktop icon and all should work. Currently do not have a logo for the icon but this is on the to do list.

RPi LCD Brightness Widget

I was surprised there was no way to adjust the backlight brightness out of the box for the official 7″ LCD (except for the command line obviously) so I made this widget to accomplish it.

Files available at my github:

First of all LCD brightness can be adjusted in the terminal using:

sudo sh -c 'echo "100" > /sys/class/backlight/rpi_backlight/brightness'

The range is 0-255 but nothing seems to happen after 200, if even get a little dimmer so my widget scales from 0-200. Put the .py & .png files in /home/pi/code directory. Put the .desktop file on your desktop. Make the files executable by:

cd /
chmod +x /home/pi/code/
chmod +x /home/pi/Desktop/brightness.desktop

The Desktop shortcut will work now but there was an annoying warning every time opening the file asking if wanted to execute the file in terminal etc., I got rid of it by opening the file manager, Go to Edit/Preferences/General, Check box for “Don’t ask options on launch executable file”

Now we have a shortcut that opens up the app to adjust the brightness but I wanted a taskbar shortcut:

Copy the .desktop file into the below two locations: (thanks to for guidance on this)

cp /home/pi/Desktop/brightness.desktop /usr/share/raspi-ui-overides/applications/
cp /home/pi/Desktop/brightness.desktop /usr/share/applications/

Open /home/pi/.config/lxpanel/LXDE-pi/panels/panel and add the below code:

nano /home/pi/.config/lxpanel/LXDE-pi/panels/panel
    Button {

Restart GUI without a full reboot:

 lxpanelctl restart && openbox --restart

All done, the shortcut should now be on the taskbar. Delete the desktop shortcut if not needed.

One improvement left to do would be to have the widget automatically set maybe 50% brightness in the event it was accidentally set to 0 previously.