Setup and use Raspberry Pi 3 in headless mode with raspbian lite

Hi, this is a problem which I have faced a lot because I don' have a external monitor. Every-time I install raspbian in my Raspberry Pi 3 board, after installing I need to connect the board to a HDMI monitor or TV for it's initial config and even to enable the serial console. I searched online for a soultion to this problem and found those but they were all scattered in bitds and pieces. So I decided to document the whole process for my refernce and also if can help others. (The process was document on DATE: 24-02-2019, linux : 4.14, OS: raspbian lite)

Things needed

• Raspberry pi 3 board and power supply (obvious)
• PC (that's obvious too)
• Internet connection (else how will you download the image)
• USB to serial converter (to make life simple)
• Ethernet cable (optional)

Here comes the process,

1. Download from raspberry pi website.

2. Extract the image.

3. Insert SD card to your system

4. Flash it with zero ( I'm giving an for Linux, for windows figure it yourself)
   Warning This command is very dangerous and your whole system might get erased so use it carefully.
   “sudo dd if=/dev/zero of=/dev/sd[x] bs=1M count=100

5. Now flash the SD card with the image downloaded.
   eg: sudo dd if=[disk img] of=/dev/sd[x] bs=4M conv=fsync

6. Your card is flashed and ready to rock!!
   NOTE: Raspberry pi by default can’t be accessed headless.

7. To access headless raspberry pi after fresh OS install there are two Ethernet or Wifi

8. I will the hard way, to access via wifi. Figure out the ethernet way yourself.

9. Insert SD card to PC after flashing image

10. Go to “volume/boot” dir of SD card and create a wpa_supllicant file with your wifi
    network credentials

11. 'wpa_supplicant' file sample
    Insert these for raspbian strech
    ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
    network={
    ssid="YOUR_NETWORK_NAME"
    psk="YOUR_PASSWORD"
    key_mgmt=WPA-PSK
    }
    For raspbian jessie
    network={
    ssid="YOUR_NETWORK_NAME"
    psk="YOUR_PASSWORD"
    key_mgmt=WPA-PSK
    }

12. Create a blank blank file named “ssh”.

13. That's done for now.

14. Insert SD card, power up raspberry pi

15. Pi will automatically connect to your wifi network ( if you have followed the above steps properly).

16. Scan the IP of the pi using nmap tool (linux) using following commands (Linux systems ONLY)
    a. Open terminal
    b. sudo nmap -sn [ip range to scan]
    c. Eg “sudo nmap -sn 192.168.1.0/24”

17. ssh to rapberry pi after getting IP
    a. Default username is “pi” and password is “raspberry”
    b. “ssh pi@[IP]”

18. That's it done.

19. Enjoy with the termnal.

To access raspberry pi using minicom or any terminal emulator, we need to enable it.

1. A usb to serial converter is needed (I mentioned earlier)
2. A terminal emulator software is needed like minicom
3. ssh to the raspberry pi
4. Type “sudo raspi-config”
5. A menu comes up
6. Select interfacing options and enable serial connection
7. Reboot
8. Connect GND, Tx, Rx to GPIO 6, 8, 10 of Raspberry pi 3 to the serial converter
9. Open terminal in your host
10. “sudo minicom -wD /dev/ttyUSB[x]”
11. Baudrate for minicom 115200
12. Done