Silo-Based architectures for High Availability Application @ IPC Fall 2016

High availability is becoming a de-facto requirement of today’s applications. Customer-facing IT failures mean directly losing customer revenue and trust, as users have grown accustomed to easily switching service providers for more reliable ones. Thus, it is critical to have a healthy, performant, resilient IT structure serving as a backbone of conducting your business. But there are no textbook solutions to achieving five 9s availability. Data redundancy, computing clusters, load balancing, fail-over mechanisms, each of these individually addresses one potential issue, but none treats systems in your organisation holistically for maximising business revenue. Silos are a clever method of grouping servers in such a way that they can be scaled both horizontally and vertically, depending on the actual application needs. Most importantly, it frees you from over-optimizing the architecture upfront, by allowing fine adjustments easy to integrate in your Agile workflow.

Transcript

1. FOR HIGH AVAILABILITY APPLICATIONS SILO-BASED ARCHITECTURES Fall 2016 Georgiana Gligor / Tekkie Consulting / @gbtekkie
2. 2 Georgiana Gligor ✤ Geek. Mother. Do-er. ✤ Crafting enterprise apps ✤ Large-Scale Application Architect ✤ PHP Cluj Meetup Organiser ✤ Systems Engineering PhD Student @gbtekkie gb@tekkie.ro
4. 4 https://youtu.be/MQm5BnhTBEQ
5. 5 advantages and disadvantages AGENDA silos: a possible approach the need for high availability what is high availability (HA)?
6. Software industry is built around anticipating change. 6
7. TYPICAL APPLICATION
8. 8 SIMPLE ARCHITECTURE
11. master Frontend Business Logic Frontend Frontend Browser internet Load balancer slave reads writes 11 ADJUSTING
12. master Frontend Business Logic Frontend Frontend Browser internet Load balancer slave reads writes 12 ADJUSTING redundancy
13. master Frontend Business Logic Frontend Frontend Browser internet Load balancer slave reads writes 13 ADJUSTING resilience
14. 14 TYPICAL LAYERING
15. 15 APPLICATION ARCHITECTURE
16. HIGH AVAILABILITY
17. 17 AVAILABILITY Ability to access the system: ✤ retrieve information ✤ alter information ✤ send new data
18. https:/ /flic.kr/p/dkasBz
19. 19 THE 9s DANCE Uptime Downtime (per year) 90.000 % 36.5 days 99.000 % 3.65 days 99.900 % 8.76 hrs 99.950 % 4 hrs 23 min Amazon SLA 99.990 % 52.56 mins four nines 99.999 % 5.26 mins five nines
20. 20 IMPACT $ 144,000 / hour 3600 $ 40 / sec * =
21. 21 USER BEHAVIOUR amazon facebook youtube Alexa Rank 6 3 2 daily time on site 12:07 mins 19:27 mins 23:44 mins daily pageviews / visitor 11.83 9.38 12.84 bounce rate 21.50% 29.50% 33.50%
22. 22 HIGH AVAILABILITY TRIANGLE cost complexity risk
23. 23 DOWNTIME ✤ scheduled ➡ you ✤ unscheduled ➡ you ➡ others
24. 24 HAPPENS TO THE BEST
25. 25 MICHAEL JACKSON
26. 26 HA SYSTEM CHARACTERISTICS 1. no single points of failure 2. reliable crossover 3. detect failures as they occur
27. https://en.wikipedia.org/wiki/Point_of_sale#/media/File:Cash_Registers.JPG RELIABLE CROSSOVER
28. https://flic.kr/p/4S4uDz CHAOS MONKEY
29. 29 HA BEST PRACTICES 1. no single points of failure 2. stateless application design 3. automate infrastructure for consistency & reliability 4. clever monitoring and alerting 5. geographically distribute your machines 6. keep spare capacity to meet increasing demand
30. 30 A man’s got to know his limitations. - Dirty Harry
31. SILOS
32. 32 Departments inside a company don’t work together. - Silo Mentality https://flic.kr/p/7Sp6Wg
33. 33 TRY UPGRADE TO PHP7
34. 34 WHAT IS A SILO? ✤ frontend (Drupal, Javascript SPAs) ✤ backend (PHP services) ✤ cache 1 silo = full setup of servers that deliver the end-to-end functionality
35. 35 WHAT IS A SILO?
36. 36 SILO-BASED ARCHITECTURE
37. 37 MULTIPLE CACHES
38. 38 A/B TESTING
39. 39 GEOGRAPHICAL DISTRIBUTION
40. 40 LIVE UPGRADES
41. 41 ADVANTAGES ✤ reuse familiar tech ✤ real A/B testing ✤ no BHUF requirements ✤ no disruption => brand loyalty ✤ lower TCO ✤ simplify scalability
42. 42 DISADVANTAGES ✤ needs razor-sharp DevOps team ✤ small increase in hardware costs on kick-off ✤ adds complexity to the monitoring layer ✤ reconsider traceability ✤ different bug reproducing and hunting
43. TAKEAWAYS
45. 45 ✤ build situational awareness with clever monitoring ✤ automate outage detection ✤ powerful A/B testing ✤ think long-term TAKEAWAYS
46. 46 FURTHER READING ✤ Wikipedia HA page ✤ OpenStack’s HA concepts ✤ Merge Hemo report from FDA ✤ USA Presidential Policy Directive 21 ✤ “Beyond Legacy Code” book ✤ TechCrunch’s summary of sites affected by Michael Jackson’s death ✤ Netflix lessons learned after AWS outage ✤ Brian Adler’s talk on “Architecting for High Availability and Multi-Cloud”
47. Q & A gb@tekkie.ro @gbtekkie
48. 48 THANK YOU See You Next Time GEORGIANA GLIGOR @gbtekkie }