enabling SSH

https://randomnerdtutorials.com/installing-raspbian-lite-enabling-and-connecting-with-ssh/

add file “ssh” into boot folder

Establishing an SSH Communication

$ sudo ssh pi@192.168.178.25

user: pi, pass: pi

Shutting Down

$ sudo poweroff

https://randomnerdtutorials.com/raspberry-pi-apache-mysql-php-lamp-server/

https://www.instructables.com/Installing-LAMP-Linux-Apache-MySQL-PHP-on-a-Raspbe/

Updating and Upgrading

$ sudo apt update && sudo apt upgrade -y

Install Apache2

$ sudo apt install apache2 -y

Testing Apache installation

$ cd /var/www/html

$ ls -al

This should show “index.html”

get RasPi IP address

$ hostname -I

enter IP address into Browser → the Apache Debian page should appear

Install PHP

$ cd /var/www/html

$ sudo apt install php -y

$ sudo rm index.html

$ sudo nano index.php

Add following script into the php file:

<?php echo "hello world"; ?>

Save with Ctrl+X >> y >> Enter,or Ctrl+O >> Enter >> Ctrl+X

OR

<?php phpinfo(); ?>

OR

$ echo "<?php phpinfo ();?>" > /var/www/html/index.php

Restart Apache

$ sudo service apache2 restart

test if Apache2 is serving .php files by opening RasPi IP address in browser

if all is fine, index.php can be removed

$ sudo rm index.php

Install MySQL (MariaDB Server)

$ sudo apt install mariadb-server php-mysql -y

$ sudo service apache2 restart

$ sudo mysql_secure_installation

In all cases, answer with y

create new user “admin” with password “your_password”

$ sudo mysql --user=root --password

> create user admin@localhost identified by 'your_password';

> grant all privileges on *.* to admin@localhost;

> FLUSH PRIVILEGES;

> exit;

Important to generate user that is not limited to a certain domain!!

>grant all privileges on *.* to 'admin3'@'%';

Install phpMyAdmin

$ cd /var/www/html

$ sudo apt install phpmyadmin -y

Options:

dbconfig-common
Apache2
Configuring phpmyadmin? OK
Configure database for phpmyadmin with dbconfig-common? Yes
Password: pi

$ sudo phpenmod mysqli

$ sudo service apache2 restart

open following address

http://192.168.178.25/phpmyadmin

if “Not Found”

$ cd /var/www/html

$ sudo ln -s /usr/share/phpmyadmin /var/www/html/phpmyadmin

$ ls

>>phpmyadmin

again, open following address

http://192.168.178.25/phpmyadmin

login with username=root, password=pi

change the permissions for your /var/www/html/ folder.

$ cd ~

$ ls -lh /var/www/

$ sudo chown -R pi:www-data /var/www/html/

$ sudo chmod -R 770 /var/www/html/

$ ls -lh /var/www/

https://randomnerdtutorials.com/esp32-esp8266-raspberry-pi-lamp-server/

Create database:

esp_data
utf8mb4_general_ci

Create table by calling SQL query:

CREATE TABLE SensorData (

id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,

sensor VARCHAR(30) NOT NULL,

location VARCHAR(30) NOT NULL,

value1 VARCHAR(10),

value2 VARCHAR(10),

value3 VARCHAR(10),

reading_time TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP

)

PHP script that is responsible for receiving incoming requests from the ESP32 or ESP8266 and inserting the data into a MySQL database.

$ cd ~

$nano /var/www/html/post-esp-data.php

https://github.com/ChuckBell/MySQL_Connector_Arduino/wiki/Troubleshooting

tr to connect to msql from another computer:

$mysql -uadmin-ppi–h192.168.178.25 –port=3306

$mysql --user=admin--password=pi--host=192.168.178.25 --port=3306

$mysql --user=admin--password=pi--host= 127.0.0.1--port=3306

$mysql -uadmin-ppi-h 127.0.0.1 test_arduino

Important in case of “ERROR 2003 (HY000): Can't connect to local MySQL server through socket”

$ sudo nano /etc/mysql/mariadb.conf.d/50-server.cnf

Here, the binding address = 127.0.0.1 must be commented out!!!

https://pawelrychlicki.pl/Article/Details/65/fixing-sqlstatehy000-2002-in-the-nextcloudowncloud-with-the-mysqlmariadb-and-the-tlsssl-ubuntu-linux-1804-server

1`Configuring WiFi in headless mode`

https://www.raspberrypi.org/documentation/configuration/wireless/wireless-cli.md

https://www.seeedstudio.com/blog/2021/01/25/three-methods-to-configure-raspberry-pi-wifi/

1.1`ssh`

To enable SSH on a headless Raspberry Pi, simply place a file named “ssh”, without any extension, onto the boot partition of the SD card from another computer. This will tell Raspberry Pi to enable SSH when booting. The content of the file does not matter.

1.2`wpa_supplicant.conf`

$ sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev

update_config=1

country=<Country Code>

network={

ssid="<SSID>"

psk="<PASSWORD>"

scan_ssid=1

}

2`Arduino script for writing to MariaDB/MySQL database`

Check sketch “Complex_Insert_WiFi_BE”

3`Showing DB content as html page`

https://randomnerdtutorials.com/esp32-esp8266-raspberry-pi-lamp-server/

$ nano /var/www/html/esp-data.php

open page http://192.168.178.25/esp-data.php

3.1`esp-data.php`

<!DOCTYPE html>

<html><body>

<?php

/*

Rui Santos

Complete project details at https://RandomNerdTutorials.com/esp32-esp8266-mysql-database-php/

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files.

The above copyright notice and this permission notice shall be included in all

copies or substantial portions of the Software.

*/

$servername = "192.168.178.25";

// REPLACE with your Database name

$dbname = "test_arduino";

// REPLACE with Database user

$username = "admin3";

// REPLACE with Database user password

$password = "pi";

// Create connection

$conn = new mysqli($servername, $username, $password, $dbname);

// Check connection

if ($conn->connect_error) {

die("Connection failed: " . $conn->connect_error);

}

$sql = "SELECTnum,message,sensor_num,value,recordedFROMhello_sensorORDER BYnumDESC";

echo '<table cellspacing="5" cellpadding="5">

<tr>

<td>num</td>

<td>message</td>

<td>sensor_num</td>

<td>value</td>

<td>recorded</td>

</tr>';

if ($result = $conn->query($sql)) {

while ($row = $result->fetch_assoc()) {

$row_num= $row["num"];

$row_message= $row["message"];

$row_sensor_num= $row["sensor_num"];

$row_value= $row["value"];

$row_recorded= $row["recorded"];

// Uncomment to set timezone to - 1 hour (you can change 1 to any number)

//$row_reading_time = date("Y-m-d H:i:s", strtotime("$row_reading_time - 1 hours"));

// Uncomment to set timezone to + 4 hours (you can change 4 to any number)

//$row_reading_time = date("Y-m-d H:i:s", strtotime("$row_reading_time + 4 hours"));

echo '<tr>

<td>' . $row_num. '</td>

<td>' . $row_message. '</td>

<td>' . $row_sensor_num. '</td>

<td>' . $row_value. '</td>

<td>' . $row_recorded. '</td>

</tr>';

}

$result->free();

}

$conn->close();

?>

</table>

</body>

</html>

4`Plotting of data fromMariaDB/MySQL database`

https://randomnerdtutorials.com/visualize-esp32-esp8266-sensor-readings-from-anywhere/

$ sudo nano /var/www/html/esp-chart.php

4.1`esp-chart.php`

<!--

Rui Santos

Complete project details at https://RandomNerdTutorials.com

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files.

The above copyright notice and this permission notice shall be included in all

copies or substantial portions of the Software.

-->

<?php

$servername = "192.168.178.25";

// REPLACE with your Database name

$dbname = "test_arduino";

// REPLACE with Database user

$username = "admin3";

// REPLACE with Database user password

$password = "pi";

// Create connection

$conn = new mysqli($servername, $username, $password, $dbname);

// Check connection

if ($conn->connect_error) {

die("Connection failed: " . $conn->connect_error);

}

$sql = "SELECTnum,message,sensor_num,value,value_h,recordedFROMhello_sensorWHERE sensor_num = 0ORDER BYnumDESC limit 40";

$result = $conn->query($sql);

while ($data = $result->fetch_assoc()){

$sensor_data[] = $data;

}

$recorded= array_column($sensor_data, 'recorded');

// ******* Uncomment to convert readings time array to your timezone ********

/*$i = 0;

foreach ($readings_time as $reading){

// Uncomment to set timezone to - 1 hour (you can change 1 to any number)

$readings_time[$i] = date("Y-m-d H:i:s", strtotime("$reading - 1 hours"));

// Uncomment to set timezone to + 4 hours (you can change 4 to any number)

//$readings_time[$i] = date("Y-m-d H:i:s", strtotime("$reading + 4 hours"));

$i += 1;

}*/

$value= json_encode(array_reverse(array_column($sensor_data, 'value')), JSON_NUMERIC_CHECK);

$value_h= json_encode(array_reverse(array_column($sensor_data, 'value_h')), JSON_NUMERIC_CHECK);

$recorded= json_encode(array_reverse($recorded), JSON_NUMERIC_CHECK);

/*echo $value1;

echo $value2;

echo $value3;

echo $reading_time;*/

$result->free();

$conn->close();

?>

<!DOCTYPE html>

<html>

<meta name="viewport" content="width=device-width, initial-scale=1">

<script src="https://code.highcharts.com/highcharts.js"></script>

<style>

body {

min-width: 310px;

max-width: 1280px;

height: 500px;

margin: 0 auto;

}

h2 {

font-family: Arial;

font-size: 2.5rem;

text-align: center;

}

</style>

<body>

<h2>ESP Weather Station</h2>

<div id="chart-temperature" class="container"></div>

<div id="chart-humidity" class="container"></div>

<script>

varvalue= <?php echo $value; ?>;

varvalue_h= <?php echo $value_h; ?>;

varrecorded= <?php echo $recorded; ?>;

var chartT = new Highcharts.Chart({

chart:{ renderTo : 'chart-temperature' },

title: { text: 'BME280 Temperature' },

series: [{

showInLegend: false,

data:value

}],

plotOptions: {

line: { animation: false,

dataLabels: { enabled: true }

},

series: { color: '#059e8a' }

},

xAxis: {

type: 'datetime',

categories:recorded

},

yAxis: {

title: { text: 'Temperature (Celsius)' }

//title: { text: 'Temperature (Fahrenheit)' }

},

credits: { enabled: false }

});

var chartH = new Highcharts.Chart({

chart:{ renderTo:'chart-humidity' },

title: { text: 'BME280 Humidity' },

series: [{

showInLegend: false,

data:value_h

}],

plotOptions: {

line: { animation: false,

dataLabels: { enabled: true }

}

},

xAxis: {

type: 'datetime',

//dateTimeLabelFormats: { second: '%H:%M:%S' },

categories:recorded

},

yAxis: {

title: { text: 'Humidity (%)' }

},

credits: { enabled: false }

});

</script>

</body>

</html>

5`Using canvas.js`

https://canvasjs.com/php-charts/multiseries-chart/

6`External access to LAMP server`

port 22 (ssh), port 80 (http)

https://raspberrypi.stackexchange.com/questions/105080/how-to-remote-to-raspberry-pi-from-outside-local-network

https://howtoraspberrypi.com/enable-mysql-remote-connection-raspberry-pi/

Configure MySQL to accept external connections to Raspberry Pi

$ sudo nano /etc/mysql/my.cnf

#bind-address = 127.0.0.1<<<<< comment the line bind-address

optionallymodify the MySQL portto reduce risk of attacks, e.g.

port = 8457

$/etc/init.d/mysql restart

7`RasPi as Samba server`

https://aallan.medium.com/adding-an-external-disk-to-a-raspberry-pi-and-sharing-it-over-the-network-5b321efce86a

SMB is the best protocol for use on multiple platforms due to superior interoperability

in case of issue “chown: changing ownership of '...': Operation not permitted”:

https://stackoverflow.com/questions/25559700/chown-command-returning-operation-not-permitted

get uid:

$ cat /etc/passwd |grep pi

get gid:

$ cat /etc/group |grep pi

Give pi:pi access to the entire /mnt/usbmount:

$ sudo mount -o remount,gid=<pi's gid>,uid=<pi's uid>/mnt/usb

Attention:FAT file system doesn't support such permissions, so they can't be applied after the drive is mounted

https://raspberrypi.stackexchange.com/questions/40408/how-to-change-permissions-on-external-hard-drive-connected-to-raspberry

Instead, drive should be formatted with pi userand/or ntfs file sstem?

Mounting USB drivethat isNTFS???-formattedunder specific name:

$ sudofdisk -l

$ sudo umount/dev/sda1

$ sudo mkdir /mnt/usb

$ sudo chown -R pi:pi /mnt/usb

seems like this command has to be used each time the usb drive is connected:$sudo mount /dev/sda1 /mnt/usb -o uid=pi,gid=pi

append following text to this file for automatic mounting under the specified path:

$ sudo nano/etc/fstab

/dev/sda1 /mnt/usb auto defaults,user 0 1

OR:

/dev/sda1 /mnt/usb ntfs-3gdefaults,user,uid=1000,gid=1000,noatime 0 0

https://raspberrypi.stackexchange.com/questions/40408/how-to-change-permissions-on-external-hard-drive-connected-to-raspberry

Make the drive accessible from the networkby adding following text:

$ sudo apt-get install samba samba-common-bin

$ sudo nano /etc/samba/smb.conf

[share]

Comment= Shared Folder

Path = /mnt/usb

Browseable = yes

Writeable = Yes

only guest = no

create mask = 0777

directory mask = 0777

Public = yes

Guest ok = yes

$ chmod 1777/mnt/usb<<<< the uSB should be mounted under this name

$ sudo /etc/init.d/samba restart

sudo service smbd restart

sudo service smbd status

https://www.raspberrypi.org/forums/viewtopic.php?t=56149

$ sudo df

$ cd /media

$ sudo mkdir HDD

$ sudo nano /etc/fstab

/dev/sda1 /media/HDD ntfs-3g defaults,noatime 0 0

$ cp /etc/samba/smb.conf /etc/samba/smb.conf.bak //Make a backup of the config file

$ nano /etc/samba/smb.conf

[media]

comment = Media share

path = /media/HDD

valid users = @users

force group = users

create mask = 0660

directory mask = 0771

read only = no

sudo service samba restart

sudo useradd ChooseUsernameHere -m -G users

sudo passwd TheChosenUsername //after this choose a password for the new user

sudo smbpasswd -a TheChosenUsername //after this enter passwd again

>>>>>>>>>>>userA pi

mount in Win10/Linux/etc.assmb://192.168.178.25/

https://raspberrytips.com/format-mount-usb-drive/

Formatting USB stick with RasPi:

$ sudo fdisk -l

$ sudo fdisk /dev/sda1

Create a new partition table : g (for GPT, use help for other format)

Create a new partition : n

You can keep the default values for a single partition

Confirm with Y to remove the signature

And finally write and exit fdisk: w

$ sudo mkfs.ext4 /dev/sda1OR: $sudo mkfs.vfat /dev/sda1OR: $sudo mkfs.ntfs /dev/sda1

https://thepihut.com/blogs/raspberry-pi-tutorials/17699796-formatting-and-mounting-a-usb-drive-from-a-terminal-window

$sudo mkfs -t vfat -I /dev/sda1

$sudo mount /dev/sda1 /mnt/usb-o umask=000

$ sudo umount /mnt/usb

8`Filtering rows with SQL`

https://chartio.com/blog/simple-sql-filtering-rows/

SELECT column_name1, column_name2

FROM table_name

WHERE column_name1 operator value;

SELECT *

FROM hello_sensor

WHERE sensor_num = 0

ORDER BY `hello_sensor`.`recorded` DESC

9`Python MySQL`

9.1`Python MySQL Querying Data`

https://stackoverflow.com/questions/44634810/fastest-way-to-fetch-table-from-mysql-into-pandas

MyEngine=create_engine('[YourDatabase]://[User]:[Pass]@[Host]/[DatabaseName]', echo = True)

Downloading:

df = pd.read_sql_query('select * from [TableName]', con= MyEngine)

Uploading:

df.to_sql([TableName], MyEngine, if_exists = 'append', index=False)

9.2`Usingmysqlmodule`

https://www.mysqltutorial.org/python-mysql-query/

https://www.codespeedy.com/fetch-data-from-mysql-table-in-python-program/

https://www.krazyprogrammer.com/2020/11/fetch-and-display-data-from-mysql-using.html

pip install mysql-connector

https://www.tutorialspoint.com/python_mysql/python_mysql_select_data.htm

import mysql.connector

#establishing the connection

conn = mysql.connector.connect(

user='admin3', password='pi', host='192.168.178.25', database='test_arduino'

)

#Creating a cursor object using the cursor() method

cursor = conn.cursor()

#Retrieving single row

query= '''SELECT * fromhello_sensor'''

#Executing the query

cursor.execute(query)

#Fetching 1st row from the table

result = cursor.fetchone();

print(result)

#Fetchingfirst tworowsfrom the table

result = cursor.fetchmany(size=2);

print(result)

#Fetchingallrowsfrom the table

result = cursor.fetchall();

print(result)

#Closing the connection

conn.close()

9.3`Create table`

https://www.tutorialspoint.com/python_mysql/python_mysql_create_table.htm

import mysql.connector

#establishing the connection

conn = mysql.connector.connect(

user='root', password='password', host='127.0.0.1', database='mydb'

)

#Creating a cursor object using the cursor() method

cursor = conn.cursor()

#Dropping EMPLOYEE table if already exists.

cursor.execute("DROP TABLE IF EXISTS EMPLOYEE")

#Creating table as per requirement

sql ='''CREATE TABLE EMPLOYEE(

FIRST_NAME CHAR(20) NOT NULL,

LAST_NAME CHAR(20),

AGE INT,

SEX CHAR(1),

INCOME FLOAT

)'''

cursor.execute(sql)

#Closing the connection

conn.close()

9.4`Insert data`

https://www.tutorialspoint.com/python_mysql/python_mysql_insert_data.htm

import mysql.connector

#establishing the connection

conn = mysql.connector.connect(

user='root', password='password', host='127.0.0.1', database='mydb'

)

#Creating a cursor object using the cursor() method

cursor = conn.cursor()

# Preparing SQL query to INSERT a record into the database.

insert_stmt = (

"INSERT INTO EMPLOYEE(FIRST_NAME, LAST_NAME, AGE, SEX, INCOME)"

"VALUES (%s, %s, %s, %s, %s)"

)

data = ('Ramya', 'Ramapriya', 25, 'F', 5000)

try:

# Executing the SQL command

cursor.execute(insert_stmt, data)

# Commit your changes in the database

conn.commit()

except:

# Rolling back in case of error

conn.rollback()

# Closing the connection

conn.close()

10`Schedule periodic RasPi reboot`

https://raspberrypi.stackexchange.com/questions/2150/how-do-i-reboot-at-a-specific-time

https://smarthomepursuits.com/how-to-reboot-raspberry-pi-on-a-schedule/

$ sudo crontab -e

>>>>> choose nano editor

>>>>> enter following command at end of file fordailyreboot at 13:03:

03 13 * * * /sbin/shutdown -r now

Check time in Linux commandline:

https://www.lifewire.com/display-date-time-using-linux-command-line-4032698

$ date

11`Install KeePass`

https://keepass.info/download.html

https://sourceforge.net/p/keepass/discussion/329220/thread/17d1bd26/

sudo apt-add-repository ppa:jtaylor/keepass

sudo apt-get update

sudo apt-get install keepass2

12`Cleanthe repository of downloaded packages`

https://askubuntu.com/questions/634820/how-can-i-delete-ubuntu-temp-files-which-are-created-during-software-installatio

sudoapt-get autoclean

sudoapt-get clean

13`cleanup a /var/log/journal in Linux`

How to tell how much space is being taken?

$journalctl --disk-usage

Fix: Option 3 (RECOMMENDED!):

$ journalctl --vacuum-size=500M

This will delete old log files until the directory reaches the threshold size stipulated, in our case, 500M.

14`Change permission of mounted drive`

$sudo chmod -R 770 /media/bora/Medien

sudo mount -o rw,remount /media/bora/Medien

https://askubuntu.com/questions/948416/changing-ownership-of-read-only-file-system-i-cant-move-delete-rename-any-f

$ mount -v | grep "^/" | awk '{print "\nPartition identifier: " $1 "\n Mountpoint: " $3}'

$ sudo mount -o remount,rw /dev/sda5/media/bora/Medien

“If you are on a dual boot system and getting the error related to the read-only file system. One probable cause could be that your other system is not correctly shut down and might be in hibernation or sleep. So login to that system and shut it down properly and religion to your Linux system. this resolved the issue in my system”

1Configuring WiFi in headless mode

1.1ssh

1.2wpa_supplicant.conf

2Arduino script for writing to MariaDB/MySQL database

3Showing DB content as html page

3.1esp-data.php

4Plotting of data from MariaDB/MySQL database

4.1esp-chart.php

5Using canvas.js

6External access to LAMP server

7RasPi as Samba server

8Filtering rows with SQL

9Python MySQL

9.1Python MySQL Querying Data

9.2Using mysql module

9.3Create table

9.4Insert data

10Schedule periodic RasPi reboot

11Install KeePass

12Clean the repository of downloaded packages

13cleanup a /var/log/journal in Linux

14Change permission of mounted drive

1`Configuring WiFi in headless mode`

1.1`ssh`

1.2`wpa_supplicant.conf`

2`Arduino script for writing to MariaDB/MySQL database`

3`Showing DB content as html page`

3.1`esp-data.php`

4`Plotting of data fromMariaDB/MySQL database`

4.1`esp-chart.php`

5`Using canvas.js`

6`External access to LAMP server`

7`RasPi as Samba server`

8`Filtering rows with SQL`

9`Python MySQL`

9.1`Python MySQL Querying Data`

9.2`Usingmysqlmodule`

9.3`Create table`

9.4`Insert data`

10`Schedule periodic RasPi reboot`

11`Install KeePass`

12`Cleanthe repository of downloaded packages`

13`cleanup a /var/log/journal in Linux`

14`Change permission of mounted drive`