highly available drupal on a raspberry pi cluster

Highly Available Drupal on a Raspberry Pi Cluster

Jeff Geerling, php[tek] 2016 (geerlingguy)

http://www.shockinglydelicious.com/dorothys-fresh-raspberry-pie-recipe/

http://www.shockinglydelicious.com/dorothys-fresh-raspberry-pie-recipe/

The Big Question

Can you run a Fortune 500 website in your basement?

Another Question

Why would you?

Gateway 2000 486 PC, RedHat Linux 6

1999

Whistle Interjet, running FreeBSD 4

Raspberry Pi 1 model B

Problems with one Pi

Problems with one Pi

• No redundancy

Problems with one Pi

• No redundancy

• microSD card reliability

Problems with one Pi

• No redundancy

• microSD card reliability

• No database backup

Problems with one Pi

• No redundancy

• microSD card reliability

• No database backup

• Limited resources

• No redundancy

• microSD card reliability

• No database backup

• Limited resources

High AvailabilitySingle Pi Multi Pi

• Easy redundancy• No redundancy

• microSD card reliability

• No database backup

• Limited resources

High AvailabilitySingle Pi Multi Pi

• Easy redundancy

• Can hot-swap a Pi

• No redundancy

• microSD card reliability

• No database backup

• Limited resources

High AvailabilitySingle Pi Multi Pi

• Easy redundancy

• Can hot-swap a Pi

• Hot database backup

• No redundancy

• microSD card reliability

• No database backup

• Limited resources

High AvailabilitySingle Pi Multi Pi

• Easy redundancy

• Can hot-swap a Pi

• Hot database backup

• Each server optimized

• No redundancy

• microSD card reliability

• No database backup

• Limited resources

High AvailabilitySingle Pi Multi Pi

2014

CPU 20 cores / 6 GHz

RAM 5 GB

Storage 80 GB microSD

Network 10/100 over Gig

www.pidramble.com

Raspberry Pi Cluster

Problem

How do you wrangle all these Pis?

“Configuration management for humans.”

“Configuration management for humans.”

___________<Andcows!>-----------\^__^\(oo)\_______(__)\)\/\||----w|||||

Source: https://flic.kr/p/nkcFoU

Demo

How did it do?

Benchmarks

Benchmark Standard

Uptime 99.95%

Max page loads/sec 1000

Power Consumption 0.5 Gflops/watt

Benchmarks - Uptime

(as measured by Server Check.in)

Benchmarks - Performance

Nginx, Cached Page 3160 req/s

Drupal, Cached Page 34 req/s

Drupal, Uncached Page 12 req/s

For comparison: • My MacBook Air: 6x faster • DigitalOcean droplets: 10x faster

Benchmarks - Power

Raspberry Pi 3 260 mA

Raspberry Pi 2 220 mA

Raspberry Pi Zero 80 mA

(power draw at idle)

Benchmarks - Power

Raspberry Pi 2 0.15 Gflops/watt

For comparison: • Core i7: 0.5 Gflops/watt

Source: http://www.phoronix.com/scan.php?page=article&item=raspberry-pi-burst&num=3

*

Go Small or Go Home

Lessons Learned

Lessons Learned

Test one change at a time.Rinse and repeat.

Lessons Learned

Networks are always reliable.

Lessons Learned

Networks are always reliable.NEVER!

The Big Question

Can you run a Fortune 500 website in your basement?

Resources

• www.pidramble.com

• Jeff Geerling's Blog

• Win the Pi Zero! Subscribe onwww.ansiblefordevops.com