Getting started with Raspberry Pi

If you are using raspberry pi for the first time; then this post might be helpful to setup the device.

In this post I’ll cover

Installing Raspbian/Ubuntu on the SD card

First of all download the image of the os you want to install on the SD card from raspberrypi.org/downloads.

If the file that you have downloaded is a zip file; then extract the contents of that file and find the .img file in it. this is the file we are going to install on the SD card.

Run following command to get the block device for SD card.

$ df
Filesystem     1K-blocks     Used Available Use% Mounted on
udev             4032932        0   4032932   0% /dev
/dev/sda5       39240312 19431624  17792332  53% /
/dev/sda6       78611376 73607668    987376  99% /home
/dev/mmcblk0    15542944        8  15542936   1% /media/x-dev/3CAC-7C20

Here in the last line it says /dev/mmcblk0 this is the device file for SD card.

You will see that this device is mounted at /media/user/some-directory if you are working on ubuntu

or at /run/media/user/some-directory if you are working on Fedora.

You need to unmount these partitions before you proceed by running:

# umount </path/to/device>

# for example on ubuntu you have to run
$ umount /media/x-dev/3CAC-7C20

# on fedora the command will be something like
$ umount /run/media/<user>/partition

Now you can install the .img that you have downloaded on to the SD card by using:

$ sudo dd bs=4M if="OS-Image-file.img" of=/dev/mmcblk0 status=progress

dd stands for data duplicator. There is an alternative for this tool. It’s dcfldd

The dd command will take a while to complete. Once it is done you can insert the SD card in RaspberryPi and start using it.

However if you don’t have a monitor you will need to configure the ssh and wifi connection to use the device.

Connecting the device to wifi network

Keep the memory card inserted; make sure that the partitions are mounted.

also keep in mind whatever changes we are making should be on the files in /etc in the memory card and not in the files in /etc on your computer.

$ cd /media/user/root-of-rpi-os

$ vim etc/network/interfaces

add the following code to this file under wlan0 block

auto wlan0
allow-hotplug wlan0
iface wlan0 inet manual
    wpa-ssid "your-ssid"
    wpa-psk "your-password"
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

after this your device should connect to the wifi network automatically once it is started.

Enable ssh on the raspberry pi

$ cd /media/user/root-of-rpi-os
$ touch etc/SSHFLAG
$ vim etc/rc.local

Now add the following code just before exit 0 line

if [ -e /etc/SSHFLAG ]; then  
  /usr/sbin/update-rc.d -f ssh defaults
  /bin/rm /etc/SSHFLAG
  /sbin/shutdown -r now
fi
  
sudo /etc/init.d/ssh start

this will enable the ssh on your raspberry pi.

Now insert the SD card in to raspberry pi and you are good to go.

you can check the ip address of your raspberry pi in the router’s connected device and start using Raspberry pi over ssh.