###Definition
The Raspberry Pi is a credit-card sized computer containing at least 1 USB slot, which can be used for any USB device containing a linux driver. Since the inception of the Raspberry Pi (model A) in February 2012, there have been two additional models made available, the model B, and the model B+.
The major schematic are as follows:
| Model A | Model B | Model B+ | Model 3B | Model Zero |
---------------:| --------------|:-------------:|:--------------:|:--------------:| --------------:| Processor | 700 MHz | 900 MHz | 700 MHz | 1.2 GHz | 1 GHz | RAM | 256 MB | 1 GB | 512 MB | 1 GB | 512 MB | USB Ports | Single USB | Quad USB | Quad USB | Quad USB | Double Micro |
Note: one of the micro usb ports, on the model zero, is required for a power source.
Numerous linux-based operating systems can be run on the Raspberry Pi. The Rasbian is generally preferred, since it is tailored specific to the Pi. Other operating systems such as Risc, Plan 9, Android, and Arch is just as savy. Though, not recommended, linux distributions such as Ubuntu will work. Keep in mind, the requirements of such operating systems tend to require more resources than the Pi has to offer (so grab an older distro).
###Overview
##Installation
###Linux Packages
The following packages need to be installed through terminal:
# Update / GIT Core
sudo apt-get update
sudo apt-get install git-core
# Python Package Manager:
sudo apt-get install python-setuptools
sudo easy_install pip
# LAMP (with phpmyadmin):
sudo apt-get install apache2
sudo apt-get install mysql-server mysql-client
sudo apt-get install php5 php5-mysql libapache2-mod-php5
sudo apt-get install phpmyadmin
# Python MariaDB / MySQL Connector:
sudo apt-get install python-mysqldb
# FTP
sudo apt-get install vsftpd
Note: This project assumes Raspbian (i.e. Wheezy) as the operating system. To upgrade to the newer Jessie distribution, modify the following:
sudo pico /etc/apt/sources.list
by changing any reference(s) of wheezy to jessie. Then, upgrade the distribution:
sudo apt-get dist-upgrade
The above upgrade would allow the use of MariaDB, in place of its predecessor MySQL. Therefore, the above:
...
sudo apt-get install mysql-server mysql-client
...
would be replaced by the following:
...
sudo apt-get install mariadb-server mariadb-client
...
##Configuration
###SD Boot Partition
The SD Card is an important and integral part of the Raspberry Pi. When a power supply is provided, the Raspberry Pi seeks a boot loader partition from its SD Card slot. If either the SD Card, or boot loader partition is absent, the Raspberry Pi will not start-up.
To ensure the presence of a boot loader partition, an acceptable linux distribution image must be placed on the SD Card. The following are the necessary steps to add the Raspbian (Wheezy) image:
# create temporary directory
$ sudo mkdir /raspbian/
$ cd /raspbian/
# install 'Raspbian' image (not on SD card)
$ sudo wget -P /raspbian/ http://downloads.raspberrypi.org/raspbian_latest
$ ls
raspbian_latest
$ sudo unzip raspbian_latest
$ ls
2014-09-09-wheezy-raspbian.img raspbian_latest
# get partition listing
$ diskutil list
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *1.0 TB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 999.3 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
/dev/disk1
#: TYPE NAME SIZE IDENTIFIER
0: Apple_partition_scheme *27.9 MB disk1
1: Apple_partition_map 32.3 KB disk1s1
/dev/disk2
#: TYPE NAME SIZE IDENTIFIER
0: FDisk_partition_scheme *7.8 GB disk2
1: DOS_FAT_32 SD-RPI 7.8 GB disk2s1
# copy 'Raspbian' image to SD card
$ sudo diskutil unmountDisk /dev/disk2
$ sudo dd if=2014-09-09-wheezy-raspbian.img | sudo pv | sudo dd of=/dev/rdisk2 bs=1m
6400000+0 records in6MiB/s] [ <=> ]
6400000+0 records out
3276800000 bytes transferred in 248.722375 secs (13174528 bytes/sec)
3.05GiB 0:04:08 [12.6MiB/s] [ <=> ]
0+50020 records in
0+50020 records out
3276800000 bytes transferred in 248.744377 secs (13173363 bytes/sec)
# delete temporary directory
$ sudo rm -rf /raspbian/
Note: dd may take up to 20mins, with pv displaying a transfer rate between 3.9-5.23MiB/s. For example, when using Dane-Elec (Class 4), the transfer rate is about 11 minutes. This is reasonable, since the SD card is expected to have a minimum transfer rate of 4MiB/s. However, a SanDisk with 48MiB/s capacity would write the Raspbian image in roughly 4 minutes (as shown above).
Note: if bs=1m was included only before the first pipe, or excluded entirely from the command, the transfer rate could vary between 660-740KiB/s (Dane-Elec, Class 4), or roughly 8x slower.
Note: if sudo dd of=/dev/disk2 was used instead of sudo dd of=/dev/rdisk2, the transfer rate could be 1MiB/s (Dane-Elec, Class 4), or roughly 5x slower.
###USB System Partition
The system partition is the disk partition that contains the operating system folder, known as system root. By default, in Linux, operating system files are mounted at / (the root directory).
The Raspberry Pi requires the boot loader partition to be located on the SD card. However, the system partition can be stored on any another medium, such as the USB flash drive.
The steps required to install a system partition on a USB flash drive, is similar to the earlier configured boot partition on the SD card. Plug in the USB flash drive to a computer, format the drive to MS-DOS (FAT), then open up terminal:
$ diskutil list
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *500.1 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 499.2 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
/dev/disk3
#: TYPE NAME SIZE IDENTIFIER
0: FDisk_partition_scheme *3.9 GB disk3
1: Windows_FAT_32 boot 58.7 MB disk3s1
2: Linux 3.2 GB disk3s2
/dev/disk4
#: TYPE NAME SIZE IDENTIFIER
0: FDisk_partition_scheme *64.0 GB disk4
1: DOS_FAT_32 USB-RPI-1 64.0 GB disk4s1
$ sudo diskutil unmountDisk /dev/disk4
Unmount of all volumes on disk4 was successful
$ sudo dd if=2014-09-09-wheezy-raspbian.img | sudo pv | sudo dd of=/dev/rdisk4s1 bs=1m
6400000+0 records in7MiB/s] [ <=>]
6400000+0 records out
3276800000 bytes transferred in 650.785056 secs (5035149 bytes/sec)
3.05GiB 0:10:50 [ 4.8MiB/s] [ <=> ]
0+50007 records in
0+50007 records out
3276800000 bytes transferred in 650.881670 secs (5034402 bytes/sec)
Once the USB flash drive contains a system partition, specifically the Raspbian operating system, the boot loader partition on the SD card, needs to know where this system partition is located. In terminal, open cmdline.txt from the earlier configured SD Card (boot partition):
cd /Volumes/boot/
sudo pico cmdline.txt
Note: on linux distributions, navigate to /media/boot/ subdirectory to modify cmdline.txt.
Next, modfiy the contents of cmdline.txt:
dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait
by changing the root variable as follows:
dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/sda2 rootfstype=ext4 elevator=deadline rootwait
This modifies the boot sequence, and tells the Raspberry Pi to boot the system partition from the USB flash drive, instead of the SD card. By default, the earlier configured SD card would boot the existing Raspbian operating system already on it. Now, after the Raspberry Pi has booted, the SD card could be removed, or unmounted. This means, the SD card is only needed during the initial boot.
###SSH Server
Secure Shell (SSH), sometimes known as Secure Socket Shell, is a network protocol which allows a client to remotely connect to a host machine over a secure channel. This secure channel, many times over an insecure network, allows the client to run various commands on the designated host machine.
To enable the SSH protocol on the Raspberry Pi, enter the following in terminal:
$ sudo raspi-config
Scroll down to the ssh option, Enable or disable ssh server, hit enter, and select Enable.
###FTP Server
A file transfer protocol (FTP) can be used to transfer files from one host, to another host machine over a TCP-based network (i.e. internet). Specifically, the raspberry pi can be enabled with an FTP server. This would allow files to be exchanged with other machines.
To enable an FTP server on the raspberry pi, the file vsftpd.conf must be edited:
$ sudo pico /etc/vsftpd.conf
Specifically, the following lines need to be changed:
anonymous_enable=YEStoanonymous_enable=NO#local_enable=YEStolocal_enable=YES#write_enable=YEStowrite_enable=YES
Then, force_dot_files=YES must be added to the bottom of the file, before restarting the FTP server:
$ sudo service vsftpd restart
###GIT
Since we installed GIT earlier, we have to remember to configure our GIT user. Only change the values within the double quotes (remove the quotes for the email):
git config --global user.email "[email protected]"
git config --global user.name "YOUR-NAME"
Fork this project in your GitHub account, then clone your repository:
cd /var/www/html/
sudo git clone https://[YOUR-USERNAME]@github.com/[YOUR-USERNAME]/raspberry-pi.git [PROJECT-NAME]
Then, change the file permissions for the entire project by issuing the command:
cd /var/
sudo chown -R jeffrey:sudo www
Note: change 'jeffrey' to the user account YOU use.
Then, add the Remote Upstream, this way we can pull any merged pull-requests:
cd /var/www/html/raspberry-pi/
git remote add upstream https://github.com/[YOUR-USERNAME]/raspberry-pi.git
####GIT Submodule
We need to initialize our git submodules:
sudo git submodule init
sudo git submodule update
The above two commands will update submodules within the cloned repository, according to the versioned master branch. If they are already initialized in the cloned repository, then the latter command will suffice.
The following updates submodule(s):
cd /var/www/html/raspberry-pi/
git checkout -b NEW_BRANCH master
cd [YOUR_SUBMODULE]/
git checkout master
git pull
cd ../
git status
to the latest code-base, within the cloned repository branch, NEW_BRANCH.
###Static IP
By default, the Raspberry Pi is assigned a dynamic IP address. This means, each time the raspberry pi boots up, a new IP address is assigned to it. Many times, however, it is more useful to have a fixed, static IP address.
The first step to acquiring a static ip is to list the network interface currently available:
$ cat /etc/network/interfaces
auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp
The line that reads iface etho0 inet dhcp, specifically dhcp, indicates that the IP address is being dynamically created by the router.
Now, more information on the router is needed:
$ ifconfig
eth0 Link encap:Ethernet HWaddr b8:27:eb:09:af:96
inet addr:192.178.71.179 Bcast:192.178.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:461 errors:0 dropped:0 overruns:0 frame:0
TX packets:492 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:42776 (41.7 KiB) TX bytes:332384 (324.5 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:33 errors:0 dropped:0 overruns:0 frame:0
TX packets:33 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2592 (2.5 KiB) TX bytes:2592 (2.5 KiB)
The following from above are important:
eth0 Link encap:Ethernet HWaddr b8:27:eb:09:af:96
inet addr:192.178.71.179 Bcast:192.178.1.255 Mask:255.255.255.0
Specifically, these values:
inet addr - 192.178.71.179
Bcast - 192.178.1.255
Mask - 255.255.255.0
Also, two additional pieces of information are needed:
$ netstat -nr
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 192.168.1.254 0.0.0.0 UG 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
Specifically, the values:
Gateway - 192.168.1.254
Destination - 192.168.1.0
Finally, plug the determined values into the Raspberry Pi's network configuration file:
$ sudo pico /etc/network/interfaces
Specifically, change the line that reads:
iface eth0 inet dhcp
to the following:
iface eth0 inet static
Then, add the values found earlier directly below it:
address 192.178.71.179
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.178.1.255
gateway 192.168.1.254
Finally, reboot the machine:
$ sudo reboot
Note: check ifconfig as needed, to see if the above changes are reflected. If not, most likely a typo needs to be fixed.
##Testing / Execution
###Test Scripts