Installing a Cluster of Raspberry Pis

What is a Raspberry Pi?

Single board computer Designed to promote teaching of computer science As of November 2016, 11 million units sold Raspberry Pi 3 Model B - $35!!

Raspberry Pi Stats

1.2 GHz quad-core ARM 64/32 bit capable

1 GB RAM 1 MicroSD slot

4 USB ports

100 Mbit Ethernet HDMI

Bluetooth Wireless LAN

Audio / Composite video out

Camera header Display header

40 pins of general-purpose I/O

Raspberry Pi Software

Supports Linux Debian (“Raspbian”)

•  Main software release CentOS 7.x

•  Only 32-bit for now Many other distributions too And now Stacki!

Stacki Ace

The best ARM on your team is an Ace Stacki pallet for ARM

•  Based on Stacki 4.0 Stacki-ace pallet for ARM

•  Raspberry Pi specific configuration

Why Stacki Ace?

Great marketing vehicle X86_64 rules the server space •  But 15 billion ARMs shipped in 2015

Can install a datacenter with a $35 device Interesting new use cases •  Low-cost pooled storage •  IoT

Stacki Ace – What does it do?

Converts a Raspberry Pi into a Stacki frontend Stacki Ace frontend can install: •  Other Raspberry Pis (“ace” appliances) •  Traditional x86_64 servers (“backend”

appliances)

What We Are Going To Do Today We are going to use a pre-installed Stacki Ace Frontend to build 3 Stacki Ace Backends

Stacki Ace Frontend (rasp002)

Network Switch

Stacki Ace Backend (rasp003)

Stacki Ace Backend (rasp004)

Stacki Ace Backend (rasp005)

Install Stacki Ace Backends

How We Installed the Stacki Ace Frontend

Frontend Installation

Download “stacki-centos.img”:

Copy “stacki-centos.img” to a MicroSD card: Boot the Raspberry Pi that will be the frontend with the MicroSD card

wget \ http://stacki.s3.amazonaws.com/public/pallets/4.1/open-source/ace/stacki-centos.img

dd if=stacki-centos.img of=/dev/sdd

Frontend Installation

When the frontend boots, login as “root” •  Password is: “stacki-centos”

•  You’ll be asked to change the password Download the Stacki Ace pallets:

wget http://stacki.s3.amazonaws.com/public/pallets/4.1/open-source/ace/os-7.3-7.x.armv7hl.disk1.iso wget http://stacki.s3.amazonaws.com/public/pallets/4.1/open-source/ace/stacki-4.1-7.x.armv7hl.disk1.iso wget http://stacki.s3.amazonaws.com/public/pallets/4.1/open-source/ace/stacki-ace-4.1-7.x.armv7hl.disk1.iso

Frontend Installation

Download and run “frontend-install.py”: This converts vanilla CentOS to a Stacki Ace frontend

wget http://stacki.s3.amazonaws.com/public/pallets/4.1/open-source/ace/frontend-install.py ./frontend-install.py --stacki-iso=stacki-4.1-7.x.armv7hl.disk1.iso \ --stacki-version=4.1 --stacki-name=stacki \ -–extra-iso=os-7.3-7.x.armv7hl.disk1.iso

Frontend Installation

Frontend Installation

Frontend Installation

Frontend Installation

Frontend Installation

Frontend Installation

Install the “stacki-ace” and “os” pallets: Apply the “stacki-ace” pallet: Stacki Ace frontend can now build Stacki Ace backend nodes

stack add pallet os-7.3-7.x.armv7hl.disk1.iso stack enable pallet os stack add pallet stacki-ace-4.1-7.x.armv7hl.disk1.iso stack enable pallet stacki-ace

stack run pallet stacki-ace | bash -x

Refresher We are going to use a pre-installed Stacki Ace Frontend to build 3 Stacki Ace Backends

Stacki Ace Frontend (rasp002)

Network Switch

Stacki Ace Backend (rasp003)

Stacki Ace Backend (rasp004)

Stacki Ace Backend (rasp005)

Contact

For More Info On Stacki Ace

GitHub for downloads and documentation:

Join our Slack channel and our Google Group: Questions? Email me:

https://github.com/StackIQ/stacki-ace

https://www.stackiq.com/support/

greg.bruno@stackiq.com

Internals

Basic Kickstart File Processing

Wrote a “kickstart interpreter” for CentOS ARM • No kickstart on CentOS ARM

Dynamically create a valid kickstart file and send it back to the Pi • Pre • Package • Post

Storage Configuration

Set “bootdisk” parameter •  Default: mmcblk0 (the MicroSD card) •  USB storage: sda

Can install onto:

•  MicroSD card •  USB-connected hard disk •  USB stick

Note: If you install onto a USB device, you no longer need a MicroSD card

Kickstart File Processing

During an install, NFS mount “/” from the frontend •  This allows for the backend Pi to be “off” the storage so we can

repartition and reformat “/boot” and “/” We configure /etc/dhcp/dhcpd.conf to answer Raspberry Pi DHCP requests • Which we automatically enable via

“program_usb_boot_mode=1” in /boot/config.txt

Basic Kickstart File Processing

On each boot, backend asks for kickstart file Looks at attributes section for “bootaction” attribute If “bootaction” == “install”, then parse and execute the kickstart file •  Otherwise, do nothing

Future

Avalanche Package Installation • Benefits x86_64 too •  Parallel file distribution on running hosts

Storage and partitioning spreadsheets Wireless networking