Differences between revisions 41 and 82 (spanning 41 versions)

RaspberryPi

Contents

RaspberryPi
raspberry pi 2 model b
1. issues ext4 fs error
2. FreeBSD 14.3 armv7

https://www.raspberrypi.org/
https://en.wikipedia.org/wiki/Raspberry_Pi
Kit in https://www.chiptec.net/pcs-e-mobilidade/computadores/raspberrypi/kit-raspberry-pi-3-modelo-b-noobs-caixa-carregador-preto.html (Kit Raspberry Pi 3 Modelo B+(NOOBS+Caixa+Carregador) Preto)
Raspberry Pi 3 Model B Plus Rev 1.3

Processador     
  Broadcom BCM2837B0, Cortex-A53 (ARMv8) 64-bit SoC @ 1.4GHz
Memória RAM     
  1GB LPDDR2 SDRAM
Armazenamento   
  Cartão MicroSD 32GB com NOOBS
Wi-Fi e Bluetooth       
  2.4GHz e 5GHz IEEE 802.11.b/g/n/ac wireless LAN, Bluetooth 4.2, BLE
LAN     
  Gigabit Ethernet em USB 2.0 (saída máxima 300 Mbps)
Expansão        
  Extended 40-pin GPIO header
  CSI camera port
  DSI display port
  4-pole stereo output e composite video port
Portas  
  HDMI 
  USB 2.0 (4) 
  Micro-SD
Alimentação     
  Entrada 5V/2.5A DC
Prazo de Garantia       
  2 Anos

BCM2835

Timers
Interrupt controller
GPIO
USB
PCM / I2S
DMA controller
I2C master
I2C / SPI slave
SPI0, SPI1, SPI2
PWM
UART0, UART1

Install and configure screensaver and lock screen

sudo apt-get install xscreensaver
Preferences, Screen saver
Auto lock after 2 minutes
Create new menu item (Preferences, Main menu editor)
- Menu item name Lock
- Command: xscreensaver-comand -lock
- Icon: /usr/share/lxpanel/images/ns-lock.png

Info

   1 lsb_release -a
   2 # No LSB modules are available.
   3 # Distributor ID:       Raspbian
   4 # Description:  Raspbian GNU/Linux 9.4 (stretch)
   5 # Release:      9.4
   6 # Codename:     stretch
   7 
   8 uname -a
   9 # Linux raspberrypi 4.14.71-v7+ #1145 SMP Fri Sep 21 15:38:35 BST 2018 armv7l GNU/Linux
  10

Install eclipse

   1 apt-get install eclipse-platform

Blink led port 26

   1 python drive_gpio26.py

   1 # drive_gpio26.py
   2 from gpiozero import LED
   3 from time import sleep
   4 
   5 led = LED(26)
   6 
   7 while True:
   8     led.on()
   9     sleep(1)
  10     led.off()
  11     sleep(1)

Install python 3.8.5 in raspberry py

   1 tar xvzf Python-3.8.5.tgz 
   2 cd Python-3.8.5/
   3 ./configure 
   4 make clean
   5 make
   6 make install
   7 sudo make install
   8 /usr/local/bin/python3.8 -v
   9 /usr/local/bin/pip3.8 install cherrypy
  10 pip3.8 install jinja2

Enable X11 forwarding

   1 # Raspberry pi side
   2 sudo nano /etc/ssh/sshd_config
   3 # add line X11Forwarding yes
   4 service ssh restart
   5 # client side
   6 ssh -X -Y userx@192.168.2.3
   7 echo $DISPLAY
   8 leafpad & # text editor
   9 pcmanfm & # file explorer
  10

Blink led service

Starts automatically after boot.

/home/pi/Documents/drive_gpio26.py

   1 from gpiozero import LED
   2 from time import sleep
   3 import os
   4 
   5 f = open('/tmp/drive_gpio26.pid','wb')
   6 f.write(str(os.getpid()))
   7 f.close()
   8 
   9 led = LED(26)
  10 
  11 while True:
  12     led.on()
  13     sleep(1)
  14     led.off()
  15     sleep(1)

/etc/init.d/drive_gpio26

   1 #! /bin/sh
   2 ### BEGIN INIT INFO
   3 # Provides:          drive_gpio26
   4 # Default-Start:     2 3 4 5
   5 # Default-Stop:
   6 # Short-Description: Blinks a led
   7 # Description:       Blinks a led
   8 ### END INIT INFO
   9 touch /var/lock/drive_gpio26
  10 # Carry out specific functions when asked to by the system
  11 case "$1" in
  12   start)
  13     echo "Starting script drive_gpio26 "
  14     su pi -c "nohup /usr/bin/python /home/pi/Documents/drive_gpio26.py >> /tmp/drive_gpio26.log 2>&1  &"
  15     ;;
  16   stop)
  17     echo "Stopping script drive_gpio26"
  18     kill $(cat  /tmp/drive_gpio26.pid)
  19     ;;
  20   *)
  21     echo "Usage: /etc/init.d/drive_gpio26 {start|stop}"
  22     exit 1
  23     ;;
  24 esac
  25 
  26 exit 0

   1 update-rc.d drive_gpio26 defaults # insert links in /etc/rc*d
   2 update-rc.d drive_gpio26 defaults 20 80
   3 update-rc.d drive_gpio26 enable
   4 service drive_gpio26 status 
   5 reboot

Install MariaDB raspbian

   1 sudo bash
   2 apt install mariadb-server
   3 mysql_secure_installation
   4 # define root pass
   5 mysql
   6 GRANT ALL ON *.* TO 'admin'@'localhost' IDENTIFIED BY '????????' WITH GRANT OPTION;
   7 FLUSH PRIVILEGES;
   8 create database testdb;
   9 show databases;
  10 use testdb
  11 CREATE TABLE locations ( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY, lat VARCHAR(30) NOT NULL, lon VARCHAR(30) NOT NULL);
  12 exit
  13 mysql -u admin -p
  14 sudo pip3.8 install mysql-connector-python
  15 #
  16 python 3.8
  17 import mysql.connector
  18 mysql.connector.connect(host='localhost',database='testdb',user='admin',password='xxxxxxxx')

test_mariadb.py

   1 import mysql.connector
   2 conn = mysql.connector.connect(
   3   host='localhost',
   4   database='testdb',
   5   user='admin',
   6   password='xxxxxxxx'
   7 )
   8 cursor=conn.cursor()
   9 cursor.execute("Insert into locations (lat,lon) values(%s,%s)" , ("aaa","bbb") )
  10 conn.commit()
  11 print(cursor.rowcount, "record inserted.")

Install Squid Web Proxy

   1 sudo bash 
   2 apt update 
   3 apt install squid
   4 cd /etc/squid/
   5 cp squid.conf squid.conf.ORIG
   6 cat squid.conf.ORIG | egrep -v -e '^[[:blank:]]*#|^$' > squid.conf
   7 nano squid.conf 
   8 acl localnet src 192.168.111.0/24
   9 http_access allow Localnet 
  10 # comment http_access deny all 
  11 service squid reload
  12 #firefox manual proxy 
  13 #IP rpi: 192.168.111.222   Port: 3128
  14 #also for ftp and https
  15

Raspberry Pi Pico

Raspberry Pi Pico is a low-cost, high-performance microcontroller board with flexible digital interfaces.

Connect with micro-usb

   1 sudo dmesg
   2 # [ 3570.065996] usb 1-4.3: Product: RP2 Boot
   3 # [ 3570.066006] usb 1-4.3: Manufacturer: Raspberry Pi
   4 # [ 3570.066016] usb 1-4.3: SerialNumber: E0C9xxxxxxxx
   5 # [ 3570.163372] usb-storage 1-4.3:1.0: USB Mass Storage device detected
   6 # [ 3570.164049] scsi host2: usb-storage 1-4.3:1.0
   7 # [ 3570.164381] usbcore: registered new interface driver usb-storage
   8 # [ 3570.180142] usbcore: registered new interface driver uas
   9 # [ 3571.192940] scsi 2:0:0:0: Direct-Access     RPI      RP2              3    PQ: 0 ANSI: 2
  10 # [ 3571.194468] sd 2:0:0:0: Attached scsi generic sg1 type 0
  11 # [ 3571.195164] sd 2:0:0:0: [sdb] 262144 512-byte logical blocks: (134 MB/128 MiB)
  12 # [ 3571.195818] sd 2:0:0:0: [sdb] Write Protect is off
  13 # [ 3571.195830] sd 2:0:0:0: [sdb] Mode Sense: 03 00 00 00
  14 # [ 3571.196325] sd 2:0:0:0: [sdb] No Caching mode page found
  15 # [ 3571.196335] sd 2:0:0:0: [sdb] Assuming drive cache: write through
  16 # [ 3571.217448]  sdb: sdb1
  17 # [ 3571.237585] sd 2:0:0:0: [sdb] Attached SCSI removable disk
  18

Update apt source

Set for /etc/apt/sources.list and /etc/apt/sources.list.d/raspi.list

deb http://legacy.raspbian.org/raspbian/ stretch main contrib non-free rpi

Swap 512 MB

   1 sudo bash
   2 nano /etc/dphys-swapfile
   3 # CONF_SWAPSIZE=512
   4 dphys-swapfile swapoff
   5 dphys-swapfile setup 
   6 dphys-swapfile swapon

Swap 2048 MB

   1 sudo bash
   2 nano /etc/dphys-swapfile
   3 # CONF_SWAPSIZE=2048
   4 dphys-swapfile swapoff
   5 dphys-swapfile setup 
   6 dphys-swapfile swapon

/etc/rc.local in Raspbian to init ttyACM0

   1 #!/bin/sh -e
   2 /usr/bin/logger "Initialize port ttyACMO for raspberry pico"
   3 chmod 666 /dev/ttyACM0
   4 stty -F /dev/ttyACM0 raw speed 115200 -crtscts cs8 -parenb -cstopb
   5 exit 0

raspberry pi 2 model b

Download SD image from raspios-bookworm-armhf-lite.img.xz.

raspberry pi os lite , compatible with all raspberries.

Release date: May 13th 2025
System: 32-bit
Kernel version: 6.12
Debian version: 12 (bookworm)
Size: 493MB.
SHA256 file integrity hash:a73d68b618c3ca40190c1aa04005a4dafcf32bc861c36c0d1fc6ddc48a370b6e

   1 cd ~/Downloads
   2 sha256sum 2025-05-13-raspios-bookworm-armhf-lite.img.xz 
   3 a73d68b618c3ca40190c1aa04005a4dafcf32bc861c36c0d1fc6ddc48a370b6e  2025-05-13-raspios-bookworm-armhf-lite.img.xz
   4 xz -t 2025-05-13-raspios-bookworm-armhf-lite.img.xz
   5 xz -d 2025-05-13-raspios-bookworm-armhf-lite.img.xz
   6 
   7 # connect pen card reader cr100 mitsai
   8 # https://www.worten.pt/produtos/leitor-de-cartoes-mitsai-cr100-6261364
   9 dmesg 
  10 # with micro sd inserted in the USB card reader
  11 # [ 5479.890546] usb 1-1: USB disconnect, device number 4
  12 # [ 5575.775242] usb 1-1: new high-speed USB device number 5 using xhci_hcd
  13 # [ 5575.924611] usb 1-1: New USB device found, idVendor=14cd, idProduct=125d, bcdDevice= 1.00
  14 # [ 5575.924649] usb 1-1: New USB device strings: Mfr=1, Product=3, SerialNumber=2
  15 # [ 5575.924668] usb 1-1: Product: Mass Storage Device
  16 # [ 5575.924681] usb 1-1: Manufacturer: Generic
  17 # [ 5575.924692] usb 1-1: SerialNumber: 125D20140310
  18 # [ 5575.927741] usb-storage 1-1:1.0: USB Mass Storage device detected
  19 # [ 5575.929376] scsi host2: usb-storage 1-1:1.0
  20 # [ 5576.951389] scsi 2:0:0:0: Direct-Access     Mass     Storage Device        PQ: 0 ANSI: 0 CCS
  21 # [ 5576.951954] sd 2:0:0:0: Attached scsi generic sg1 type 0
  22 # [ 5576.953584] sd 2:0:0:0: [sdb] 30547968 512-byte logical blocks: (15.6 GB/14.6 GiB)
  23 # [ 5576.953746] sd 2:0:0:0: [sdb] Write Protect is off
  24 # [ 5576.953752] sd 2:0:0:0: [sdb] Mode Sense: 03 00 00 00
  25 # [ 5576.953903] sd 2:0:0:0: [sdb] No Caching mode page found
  26 # [ 5576.953908] sd 2:0:0:0: [sdb] Assuming drive cache: write through
  27 # [ 5576.965688]  sdb: sdb1 sdb2
  28 # [ 5576.966073] sd 2:0:0:0: [sdb] Attached SCSI removable disk
  29 
  30 # prepare SD disk and partitoons
  31 cfdisk /dev/sdb
  32 #     Device                   Start             End         Sectors         Size Type
  33 # /dev/sdb1                 2048           34815           32768          16M unknown         
  34 # /dev/sdb2                34816        30547934        30513119        14.5G unknown
  35 # partitions android meta e android expand 
  36 
  37 # https://www.raspberrypi.com/documentation/computers/getting-started.html#installing-the-operating-system
  38 # https://www.nixcraft.com/t/how-to-write-rasbian-os-raspios-img-file-using-dd-to-sd-card-on-linux/3709/2
  39 # Use the dd command:
  40 sudo dd if=2025-05-13-raspios-bookworm-armhf-lite.img of=/dev/sdb bs=4M conv=fsync
  41 
  42 # While the image is being written the LED of cr100 blinks
  43 # 610+0 records in
  44 # 610+0 records out
  45 # 2558525440 bytes (2.6 GB, 2.4 GiB) copied, 442.663 s, 5.8 MB/s
  46 #     Device         Boot          Start         End     Sectors     Size    Id Type
  47 # Free space                    2048       16383       14336       7M                         
  48 # /dev/sdb1                    16384     1064959     1048576     512M     c W95 FAT32 (LBA)
  49 # /dev/sdb2                  1064960     4997119     3932160     1.9G    83 Linux
  50 # Free space                 4997120    30547967    25550848    12.2G
  51 
  52 mount /dev/sdb2 /mnt/
  53 ls /mnt/
  54 # bin   dev  home  lost+found  mnt  proc        run   srv  tmp  var
  55 # boot  etc  lib         media       opt  root  sbin  sys  usr
  56 
  57 cat  /mnt/etc/os-release 
  58 # PRETTY_NAME="Raspbian GNU/Linux 12 (bookworm)"
  59 # NAME="Raspbian GNU/Linux"
  60 # VERSION_ID="12"
  61 # VERSION="12 (bookworm)"
  62 # VERSION_CODENAME=bookworm
  63 # ID=raspbian
  64 # ID_LIKE=debian
  65 # HOME_URL="http://www.raspbian.org/"
  66 # SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
  67 # BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"
  68 umount /mnt

Inserted the micro SD card in the back fo the raspberry pi 2 board, connected HDMI, keyboard and mouse. After turning on the power it started to boot and show the linux kernel log while booting. Selected keyboard, other, Portuguese, Portuguese, new user vitor, set pwd. Got a console prompt.

Connected Ethernet cable to the tp-link router.

   1 ping -c 3 www.google.com
   2 sudo bash
   3 apt update
   4 apt upgrade
   5 apt full-upgrade
   6 apt autoremove 
   7 rpi2b.intra.bitarus.org 192.168.1.7
   8 rpi2b.bitarus.mooo.com 192.168.1.7
   9 
  10 named-checkconf /etc/bind/named.conf
  11 named-checkzone xyz.com /etc/bind/xyz.com.hosts
  12 named-checkzone zyx.org /etc/bind/zyz.org.hosts 
  13 sudo service named restart 
  14 
  15 raspinfo > /tmp/out.txt
  16 # Raspberry Pi 2 Model B Rev 1.1
  17 # PRETTY_NAME="Raspbian GNU/Linux 12 (bookworm)"
  18 
  19 sudo apt install inxi nmap rsyslog autossh
  20 inxi 
  21 # CPU: quad core ARMv7 v7l (-MCP-) speed/min/max: 900/600/900 MHz
  22 # Kernel: 6.12.25+rpt-rpi-v7 armv7l Up: 14m Mem: 212.2/997.1 MiB (21.3%)
  23 # Storage: 14.57 GiB (15.6% used) Procs: 138 Shell: Bash inxi: 3.3.26
  24

issues ext4 fs error

EXT4-fs error Cannot read block bitmap Journal has aborted
Failed to convert unwritten extents

Message from syslogd@pi2b at Oct 16 10:45:14 ...
 kernel:[ 4370.623756] EXT4-fs (mmcblk0p2): failed to convert unwritten extents to written extents -- potential data loss!  (inode 2992, error -5)

Message from syslogd@pi2b at Oct 16 10:45:14 ...
 kernel:[ 4370.651065] EXT4-fs (mmcblk0p2): failed to convert unwritten extents to written extents -- potential data loss!  (inode 131094, error -5)

https://manpages.debian.org/stretch/systemd/systemd-fsck@.service.8.en.html

fsck.repair=yes
fsck.mode=force

/boot/firmware/cmdline.txt

console=serial0,115200 console=tty1 root=PARTUUID=59fb7884-02 rootfstype=ext4 fsck.repair=yes rootwait fsck.mode=force

In debian elitedesk using pen card reader cr100 mitsai

   1 # it uses /dev/sdb partitions /dev/sdb1 and /dev/sb2
   2 fsck -fvy /dev/sdb1 
   3 fsck -fvy /dev/sdb2
   4 fsck -vck /dev/sdb2
   5 
   6 fsck -vcck /dev/sdb2 # read write non destructive
   7

If fails again try:

sudo dd of=pi2b_backup.img if=/dev/sdb bs=4M conv=fsync
then try to write it again to /dev/sdb to check if it is successful
- sudo dd if=pi2b_backup.img of=/dev/sdb bs=4M conv=fsync

   1 badblocks -sw /dev/sdb2
   2 Testing with pattern 0xaa: done                                                 
   3 Reading and comparing: done                                                 
   4 Testing with pattern 0x55: done                                                 
   5 Reading and comparing: done                                                 
   6 Testing with pattern 0xff: done                                                 
   7 Reading and comparing: done                                                 
   8 Testing with pattern 0x00: done                                                 
   9 Reading and comparing: done

No badblocks detected. Will try FreeBSD 14.3

FreeBSD 14.3 armv7

Installed FreeBSD 14.3 armv7

   1 cd ~/Downloads
   2 unxz FreeBSD-14.3-RELEASE-arm-armv7-GENERICSD.img.xz
   3 sudo dd if=FreeBSD-14.3-RELEASE-arm-armv7-GENERICSD.img of=/dev/sdb conv=sync bs=1M 
   4 
   5 vi /etc/rc.conf
   6 # keymap="pt.iso.acc.kbd"
   7 # syslogd_enable="YES"
   8 # echo "*.info /var/log/syslog" >> /etc/syslog.conf 
   9 # hostname="rpi2b"
  10 # ntpd_enable="YES"
  11 # ntpdate_enable="YES"
  12 
  13 ifconfig
  14 ping -c 3 hostx
  15 # user root pass root  root:root
  16 kbdmap
  17 adduser 
  18 # userx
  19 
  20 pw user mod userx -G wheel  # allow su - 
  21 # A pre-built version of pkg could not be found for your system 
  22 SSL_NO_VERIFY_PEER=1 pkg update 
  23 SSL_NO_VERIFY_PEER=1 pkg install sudo 
  24 SSL_NO_VERIFY_PEER=1 pkg install nano
  25 su - 
  26 export SSL_NO_VERIFY_PEER=1
  27 # Now run your command
  28 pkg upgrade
  29 pkg install ca_root_nss
  30 pkg search autossh
  31 # autossh-1.4g_1                 Automatically restart SSH sessions and tunnels
  32 SSL_NO_VERIFY_PEER=1 pkg install autossh htop 
  33 SSL_NO_VERIFY_PEER=1 pkg install openjdk11 python3 maven
  34 java -version
  35 javac -version
  36 mvn -v 
  37 python3 -V
  38 
  39 uname -a
  40 # FreeBSD generic 14.3-RELEASE FreeBSD 14.3-RELEASE releng/14.3-n271432-8c9ce319fef7 GENERIC arm
  41 SSL_NO_VERIFY_PEER=1 pkg install curl
  42 
  43 cp -v /usr/share/zoneinfo/Portugal /etc/localtime
  44 SSL_NO_VERIFY_PEER=1 pkg install bash
  45 pw user mod userx -s /usr/local/bin/bash
  46 ssh freebsd@hostx # password freebsd 
  47 
  48 nohup certctl rehash &
  49 ps uax | grep cert
  50 certctl list # the list should grow
  51 pkg search jdk # should work after a while without SSL_NO_VERIFY_PEER=1
  52 # check filesystem
  53 su - 
  54 fstyp /dev/ufs/rootfs 
  55 # ufs
  56 # https://en.wikipedia.org/wiki/Unix_File_System
  57 visudo 
  58 %wheel ALL=(ALL:ALL) ALL
  59 
  60 pw group mod wheel -m userx

-  ⇤ ← Revision 41 as of 2022-10-27 09:42:39 → 
  Size: 5991
  Editor: localhost
  Comment:
+   ← Revision 82 as of 2025-10-25 22:23:05 → ⇥
  Size: 17198
  Editor: vitor
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 2:
+<<TableOfContents(2)>>
-Line 59:
+Line 61:
-{{{
$ lsb_release -a
No LSB modules are available.
Distributor ID:	Raspbian
Description:	Raspbian GNU/Linux 9.4 (stretch)
Release:	9.4
Codename:	stretch

$ uname -a
Linux raspberrypi 4.14.71-v7+ #1145 SMP Fri Sep 21 15:38:35 BST 2018 armv7l GNU/Linux
+{{{#!highlight sh
lsb_release -a
# No LSB modules are available.
# Distributor ID:	Raspbian
# Description:	Raspbian GNU/Linux 9.4 (stretch)
# Release:	9.4
# Codename:	stretch

uname -a
# Linux raspberrypi 4.14.71-v7+ #1145 SMP Fri Sep 21 15:38:35 BST 2018 armv7l GNU/Linux
-Line 72:
+Line 74:
- * apt-get install eclipse-platform
+{{{#!highlight sh
apt-get install eclipse-platform
}}}
-Line 77:
+Line 81:
- *  python drive_gpio26.py
+{{{#!highlight sh
python drive_gpio26.py
}}}
-Line 236:
+Line 242:
+ * https://datasheets.raspberrypi.com/picow/pico-w-datasheet.pdf
-Line 237:
+Line 244:
+ * https://mauser.pt/catalog/product_info.php?cPath=1667_2620_1672&products_id=095-0598
 * https://mauser.pt/catalog/product_info.php?cPath=1667_2620_1672&products_id=095-0596
-Line 238:
+Line 247:
+=== Connect with micro-usb ===
{{{#!highlight sh
sudo dmesg
# [ 3570.065996] usb 1-4.3: Product: RP2 Boot
# [ 3570.066006] usb 1-4.3: Manufacturer: Raspberry Pi
# [ 3570.066016] usb 1-4.3: SerialNumber: E0C9xxxxxxxx
# [ 3570.163372] usb-storage 1-4.3:1.0: USB Mass Storage device detected
# [ 3570.164049] scsi host2: usb-storage 1-4.3:1.0
# [ 3570.164381] usbcore: registered new interface driver usb-storage
# [ 3570.180142] usbcore: registered new interface driver uas
# [ 3571.192940] scsi 2:0:0:0: Direct-Access     RPI      RP2              3    PQ: 0 ANSI: 2
# [ 3571.194468] sd 2:0:0:0: Attached scsi generic sg1 type 0
# [ 3571.195164] sd 2:0:0:0: [sdb] 262144 512-byte logical blocks: (134 MB/128 MiB)
# [ 3571.195818] sd 2:0:0:0: [sdb] Write Protect is off
# [ 3571.195830] sd 2:0:0:0: [sdb] Mode Sense: 03 00 00 00
# [ 3571.196325] sd 2:0:0:0: [sdb] No Caching mode page found
# [ 3571.196335] sd 2:0:0:0: [sdb] Assuming drive cache: write through
# [ 3571.217448]  sdb: sdb1
# [ 3571.237585] sd 2:0:0:0: [sdb] Attached SCSI removable disk
}}}

== Update apt source ==
Set for '''/etc/apt/sources.list''' and '''/etc/apt/sources.list.d/raspi.list'''
{{{
deb http://legacy.raspbian.org/raspbian/ stretch main contrib non-free rpi
}}}

== Swap 512 MB ==
{{{#!highlight sh
sudo bash
nano /etc/dphys-swapfile
# CONF_SWAPSIZE=512
dphys-swapfile swapoff
dphys-swapfile setup 
dphys-swapfile swapon
}}}

== Swap 2048 MB ==
{{{#!highlight sh
sudo bash
nano /etc/dphys-swapfile
# CONF_SWAPSIZE=2048
dphys-swapfile swapoff
dphys-swapfile setup 
dphys-swapfile swapon
}}}

== /etc/rc.local in Raspbian to init ttyACM0 ==
{{{#!highlight sh
#!/bin/sh -e
/usr/bin/logger "Initialize port ttyACMO for raspberry pico"
chmod 666 /dev/ttyACM0
stty -F /dev/ttyACM0 raw speed 115200 -crtscts cs8 -parenb -cstopb
exit 0
}}}

= raspberry pi 2 model b =
Download SD image from [[https://downloads.raspberrypi.com/raspios_lite_armhf/images/raspios_lite_armhf-2025-05-13/2025-05-13-raspios-bookworm-armhf-lite.img.xz | raspios-bookworm-armhf-lite.img.xz ]]. 

raspberry pi os lite , compatible with all raspberries.  
 * Release date: May 13th 2025
 * System: 32-bit 
 * Kernel version: 6.12 
 * Debian version: 12 (bookworm) 
 * Size: 493MB. 
 * SHA256 file integrity hash:a73d68b618c3ca40190c1aa04005a4dafcf32bc861c36c0d1fc6ddc48a370b6e

{{{#!highlight sh
cd ~/Downloads
sha256sum 2025-05-13-raspios-bookworm-armhf-lite.img.xz 
a73d68b618c3ca40190c1aa04005a4dafcf32bc861c36c0d1fc6ddc48a370b6e  2025-05-13-raspios-bookworm-armhf-lite.img.xz
xz -t 2025-05-13-raspios-bookworm-armhf-lite.img.xz
xz -d 2025-05-13-raspios-bookworm-armhf-lite.img.xz

# connect pen card reader cr100 mitsai
# https://www.worten.pt/produtos/leitor-de-cartoes-mitsai-cr100-6261364
dmesg 
# with micro sd inserted in the USB card reader
# [ 5479.890546] usb 1-1: USB disconnect, device number 4
# [ 5575.775242] usb 1-1: new high-speed USB device number 5 using xhci_hcd
# [ 5575.924611] usb 1-1: New USB device found, idVendor=14cd, idProduct=125d, bcdDevice= 1.00
# [ 5575.924649] usb 1-1: New USB device strings: Mfr=1, Product=3, SerialNumber=2
# [ 5575.924668] usb 1-1: Product: Mass Storage Device
# [ 5575.924681] usb 1-1: Manufacturer: Generic
# [ 5575.924692] usb 1-1: SerialNumber: 125D20140310
# [ 5575.927741] usb-storage 1-1:1.0: USB Mass Storage device detected
# [ 5575.929376] scsi host2: usb-storage 1-1:1.0
# [ 5576.951389] scsi 2:0:0:0: Direct-Access     Mass     Storage Device        PQ: 0 ANSI: 0 CCS
# [ 5576.951954] sd 2:0:0:0: Attached scsi generic sg1 type 0
# [ 5576.953584] sd 2:0:0:0: [sdb] 30547968 512-byte logical blocks: (15.6 GB/14.6 GiB)
# [ 5576.953746] sd 2:0:0:0: [sdb] Write Protect is off
# [ 5576.953752] sd 2:0:0:0: [sdb] Mode Sense: 03 00 00 00
# [ 5576.953903] sd 2:0:0:0: [sdb] No Caching mode page found
# [ 5576.953908] sd 2:0:0:0: [sdb] Assuming drive cache: write through
# [ 5576.965688]  sdb: sdb1 sdb2
# [ 5576.966073] sd 2:0:0:0: [sdb] Attached SCSI removable disk

# prepare SD disk and partitoons
cfdisk /dev/sdb
#     Device                   Start             End         Sectors         Size Type
# /dev/sdb1                 2048           34815           32768          16M unknown         
# /dev/sdb2                34816        30547934        30513119        14.5G unknown
# partitions android meta e android expand 

# https://www.raspberrypi.com/documentation/computers/getting-started.html#installing-the-operating-system
# https://www.nixcraft.com/t/how-to-write-rasbian-os-raspios-img-file-using-dd-to-sd-card-on-linux/3709/2
# Use the dd command:
sudo dd if=2025-05-13-raspios-bookworm-armhf-lite.img of=/dev/sdb bs=4M conv=fsync

# While the image is being written the LED of cr100 blinks
# 610+0 records in
# 610+0 records out
# 2558525440 bytes (2.6 GB, 2.4 GiB) copied, 442.663 s, 5.8 MB/s
#     Device         Boot          Start         End     Sectors     Size    Id Type
# Free space                    2048       16383       14336       7M                         
# /dev/sdb1                    16384     1064959     1048576     512M     c W95 FAT32 (LBA)
# /dev/sdb2                  1064960     4997119     3932160     1.9G    83 Linux
# Free space                 4997120    30547967    25550848    12.2G

mount /dev/sdb2 /mnt/
ls /mnt/
# bin   dev  home  lost+found  mnt  proc	run   srv  tmp	var
# boot  etc  lib	 media	     opt  root	sbin  sys  usr

cat  /mnt/etc/os-release 
# PRETTY_NAME="Raspbian GNU/Linux 12 (bookworm)"
# NAME="Raspbian GNU/Linux"
# VERSION_ID="12"
# VERSION="12 (bookworm)"
# VERSION_CODENAME=bookworm
# ID=raspbian
# ID_LIKE=debian
# HOME_URL="http://www.raspbian.org/"
# SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
# BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"
umount /mnt 
}}}

Inserted the micro SD card in the back fo the raspberry pi 2 board, connected HDMI, keyboard and mouse.
After turning on the power it started to boot and show the linux kernel log while booting.
Selected keyboard, other, Portuguese, Portuguese, new user vitor, set pwd. Got a console prompt.

Connected Ethernet cable to the tp-link router.
{{{#!highlight sh 
ping -c 3 www.google.com
sudo bash
apt update
apt upgrade
apt full-upgrade
apt autoremove 
rpi2b.intra.bitarus.org 192.168.1.7
rpi2b.bitarus.mooo.com 192.168.1.7

named-checkconf /etc/bind/named.conf
named-checkzone xyz.com /etc/bind/xyz.com.hosts
named-checkzone zyx.org /etc/bind/zyz.org.hosts 
sudo service named restart 

raspinfo > /tmp/out.txt
# Raspberry Pi 2 Model B Rev 1.1
# PRETTY_NAME="Raspbian GNU/Linux 12 (bookworm)"

sudo apt install inxi nmap rsyslog autossh
inxi 
# CPU: quad core ARMv7 v7l (-MCP-) speed/min/max: 900/600/900 MHz
# Kernel: 6.12.25+rpt-rpi-v7 armv7l Up: 14m Mem: 212.2/997.1 MiB (21.3%)
# Storage: 14.57 GiB (15.6% used) Procs: 138 Shell: Bash inxi: 3.3.26
}}}

== issues  ext4 fs error  ==
 * EXT4-fs error Cannot read block bitmap Journal has aborted
 * Failed to convert unwritten extents 
{{{
Message from syslogd@pi2b at Oct 16 10:45:14 ...
 kernel:[ 4370.623756] EXT4-fs (mmcblk0p2): failed to convert unwritten extents to written extents -- potential data loss!  (inode 2992, error -5)

Message from syslogd@pi2b at Oct 16 10:45:14 ...
 kernel:[ 4370.651065] EXT4-fs (mmcblk0p2): failed to convert unwritten extents to written extents -- potential data loss!  (inode 131094, error -5)
}}}
https://manpages.debian.org/stretch/systemd/systemd-fsck@.service.8.en.html
 * fsck.repair=yes
 * fsck.mode=force
/boot/firmware/cmdline.txt
{{{
console=serial0,115200 console=tty1 root=PARTUUID=59fb7884-02 rootfstype=ext4 fsck.repair=yes rootwait fsck.mode=force
}}}

In debian elitedesk using pen card reader cr100 mitsai
{{{#!highlight sh
# it uses /dev/sdb partitions /dev/sdb1 and /dev/sb2
fsck -fvy /dev/sdb1 
fsck -fvy /dev/sdb2
fsck -vck /dev/sdb2

fsck -vcck /dev/sdb2 # read write non destructive
}}}

If fails again try:
 * sudo dd of=pi2b_backup.img if=/dev/sdb bs=4M conv=fsync
 * then try to write it again to /dev/sdb to check if it is successful
  * sudo dd if=pi2b_backup.img of=/dev/sdb bs=4M conv=fsync
{{{#!highlight sh
badblocks -sw /dev/sdb2
Testing with pattern 0xaa: done                                                 
Reading and comparing: done                                                 
Testing with pattern 0x55: done                                                 
Reading and comparing: done                                                 
Testing with pattern 0xff: done                                                 
Reading and comparing: done                                                 
Testing with pattern 0x00: done                                                 
Reading and comparing: done                            
}}}
No badblocks detected. Will try FreeBSD 14.3

== FreeBSD 14.3 armv7 ==
Installed [[https://download.freebsd.org/ftp/releases/arm/armv7/ISO-IMAGES/14.3/FreeBSD-14.3-RELEASE-arm-armv7-GENERICSD.img.xz|FreeBSD 14.3 armv7]]

{{{#!highlight sh 
cd ~/Downloads
unxz FreeBSD-14.3-RELEASE-arm-armv7-GENERICSD.img.xz
sudo dd if=FreeBSD-14.3-RELEASE-arm-armv7-GENERICSD.img of=/dev/sdb conv=sync bs=1M 

vi /etc/rc.conf
# keymap="pt.iso.acc.kbd"
# syslogd_enable="YES"
# echo "*.info /var/log/syslog" >> /etc/syslog.conf 
# hostname="rpi2b"
# ntpd_enable="YES"
# ntpdate_enable="YES"

ifconfig
ping -c 3 hostx
# user root pass root  root:root
kbdmap
adduser 
# userx

pw user mod userx -G wheel  # allow su - 
# A pre-built version of pkg could not be found for your system 
SSL_NO_VERIFY_PEER=1 pkg update 
SSL_NO_VERIFY_PEER=1 pkg install sudo 
SSL_NO_VERIFY_PEER=1 pkg install nano
su - 
export SSL_NO_VERIFY_PEER=1
# Now run your command
pkg upgrade
pkg install ca_root_nss
pkg search autossh
# autossh-1.4g_1                 Automatically restart SSH sessions and tunnels
SSL_NO_VERIFY_PEER=1 pkg install autossh htop 
SSL_NO_VERIFY_PEER=1 pkg install openjdk11 python3 maven
java -version
javac -version
mvn -v 
python3 -V

uname -a
# FreeBSD generic 14.3-RELEASE FreeBSD 14.3-RELEASE releng/14.3-n271432-8c9ce319fef7 GENERIC arm
SSL_NO_VERIFY_PEER=1 pkg install curl

cp -v /usr/share/zoneinfo/Portugal /etc/localtime
SSL_NO_VERIFY_PEER=1 pkg install bash
pw user mod userx -s /usr/local/bin/bash
ssh freebsd@hostx # password freebsd 

nohup certctl rehash &
ps uax | grep cert
certctl list # the list should grow
pkg search jdk # should work after a while without SSL_NO_VERIFY_PEER=1
# check filesystem
su - 
fstyp /dev/ufs/rootfs 
# ufs
# https://en.wikipedia.org/wiki/Unix_File_System
visudo 
%wheel ALL=(ALL:ALL) ALL

pw group mod wheel -m userx
}}}