1. Architecture for Disaster Resistant Systems - Resilience (materials science) - www.mozaicworks.com 2. Me Adi Bolboac Programmer Organizational & Technical Trainer & Coach www.mozaicworks.com 3. Disaster Resistant System A system's degree of resistance to disasters is a measurement of its stability under stress conditions caused by the outside environment or by the people who manipulate it. www.mozaicworks.com 4. We will talk about Software Architecture Fligtht safety vs Product safety Risk management in Aviation vs Software Briefing in Aviation vs Software Checklists Measurements for fast feedback Tools and techniques to avoid disasters www.mozaicworks.com 5. Architecture = - Architect = chief builder www.mozaicworks.com 6. Pilot Authority and Responsibility Operate aircraft according to regulations Operate within the aircraft limitations Refuse any unsafe flight Evaluate and approve or refuse missions Before departure understands request Have all resources to perform flight www.mozaicworks.com 7. Architect Authority and Responsibility Focus on non-functional requirements (security, maintainabiliy, extensibility, scalability, usability, etc) Help the teams create standards Enforce standards Maximize reusage Modularize system with feedback from the stakeholders (eg. product roadmap, usability tests) Work closely with teams and code with them Adapt architecture depending on the feedback Responsible for the system's health (Architecture Stewardship) www.mozaicworks.com 8. Aviation Risk Management Is a five-step process 1. Identify the Hazard 2. Asses the Hazard / Risk 3. Make a Risk Decision 4. Implement Controls 5. Supervize / Evaluate www.mozaicworks.com 9. Architect Risk Management 1. Assess 2. Brainstorm 3. Assign probability 4. Estimate impact 5. Decide which to consider 6. Create contingency plan 7. Create guidelines 8. Gather feedback on guidelines 9. Enforce guidelines 10. Go to 1. www.mozaicworks.com 10. Deployment & Risk Management 1. Assess www.mozaicworks.com 11. Deployment & Risk Management 2. Brainstorm 1. Risk: Security between GUI and WS 2. Risk: Communication to Hospitals DB 3. Risk: Storage API to stop working 4. Risk: GUI to stop working 5. Risk: Cloud storage to stop working 6. Risk: WS stops working 7. Risk: ... www.mozaicworks.com 12. Deployment & Risk Management 3. Assign Probability www.mozaicworks.com 13. Deployment & Risk Management 4. Estimate Impact 1. Risk: Security between GUI and WS HIGH 2. Risk: Communication to Hospitals DB HIGH 3. Risk: Storage API to stop working MEDIUM 4. Risk: GUI to stop working HIGH 5. Risk: Cloud storage to stop working HIGH 6. Risk: WS stops working HIGH 7. Risk: ... www.mozaicworks.com 14. Deployment & Risk Management 5. Decide Which to Consider 1. Risk: Security between GUI and WS HIGH 2. Risk: Communication to Hospitals DB HIGH 3. Risk: Storage API to stop working MEDIUM 4. Risk: GUI to stop working HIGH 5. Risk: Cloud storage to stop working HIGH 6. Risk: WS stops working HIGH 7. Risk: ... www.mozaicworks.com 15. Deployment & Risk Management 6. Create Contingency Plan Risk: GUI to stop working HIGH Measure the live system performance Message suport when it fails When service stops, start automatically another service If service cannot be started, create new machine, start service and reroute to new machine Message support if failure continues for more than 5 minutes www.mozaicworks.com 16. Deployment & Risk Management 7. Guidelines Always create a deployment script Use the deployment script to automatically spawn new service Always log Always message support about system failure www.mozaicworks.com 17. Deployment & Risk Management All these practices help us to minimize the risks www.mozaicworks.com 18. Aviation Checklist Usage The checklists are used: a) Before engine start b) Before Starting c) Before takeoff d) Cruise e) Before landing f) After landing g) Engine shutdown www.mozaicworks.com 19. Checklist Before Engine Start Auxiliary fuel pump Off Flight controls Free and correct Instruments and radios Checked and set Landing gear position lights Checked Altimeter Set Directional gyro Set Fuel gauges Checked Trim Set Propeller Exercise Magnetos Checked Engine idle checked Flaps As required Seat belts/shoulder harnesses Fastened Parking brake Off www.mozaicworks.com 20. Architecture Checklist Usage What if we use checklists: a) Before project start b) Before kick-off project c) Before first sprint d) During development e) Before deployment f) After deployment g) For retrospective www.mozaicworks.com 21. Checklist Before Project Starts Requirements are clear Customer needs are identified Final user types (personas) are identified Architecture sketch finalized: system diagram, deployment diagram Architecture reviewed by another architect Architecture reviewed by QA Architecture reviewed by Operations www.mozaicworks.com 22. Checklist Before kick-off We have the minimum architecture The team members know their roles and responsibilities We have all the necessary roles in the team The team understand the business concept We have enough hardware in place All the software tools are installed and ready www.mozaicworks.com 23. Checklist Before First Sprint We have enough requirements clarified The team read and understood the requirements for the next period The architecture is clear to the team We have architecture guidelines in place Standards and team rules have been defined and improved with the team www.mozaicworks.com 24. Aviation - Measurements Pilots use tools to continously assess the current situation www.mozaicworks.com 25. Architecture - Measurements Architects should use appropriate metrics and tools to continously assess the current situation The difference: metrics need to be chosen www.mozaicworks.com 26. Architecture - Measurements Number of failing tests: Integration, Performance, Security, etc Automated = current situation Hint: Always prefer automated metrics www.mozaicworks.com 27. Architecture - Standards Code standards per language Code review standards Tool usage standards (ie commit at least once per day) Hint: use automated tools to enforce code standards (ie Sonar, Code Cop) www.mozaicworks.com 28. Architecture - Policies Security Policies Always encrypt when outside the LAN Programming policies Do not return null, always use Null Object Pattern Process Policies When the architecture is not helping, talk with the architect(s) immediately The team takes decisions about the detailed architecturewww.mozaicworks.com 29. Aviation - Practices www.mozaicworks.com - From Lufthansa magazine - Always pair when a high risk is involved! 30. Architecture - Practices www.mozaicworks.com Code review Architecture review Pair-programming Team feedback Continous improvement All these practices minimize the risks and make the system resistant to disasters 31. General Guideline Pilots Architects should not allow themselves to be persuaded to attempt anything against their better judgment. When in doubt, don't! (Operations and Safety Procedures Guide for Helicopter Pilots, page 25) www.mozaicworks.com 32. Disaster Resistant Systems www.mozaicworks.com A system is disaster resistant if we: Perform risk management before and during the project Use checklists to minimize mistakes Continously assess risks and rate impact Use transparency and honesty in the team Use always our better judgement 33. Questions? www.mozaicworks.com Let's talk at Open Space as well! 34. Thank you! adrian.bolboaca@mozaicworks.com Twitter: @adibolb Blog: blog.adrianbolboaca.ro www.mozaicworks.com See the slides at http://www.slideshare.net/adibolb 35. References http://upload.wikimedia.org/wikipedia/commons/8/84/Stress_Strain_Ductile_Material.png Lufthansa Magazine http://www.nifc.gov/aviation/av_documents/av_helicopters/SafetyBrief.pdf http://upload.wikimedia.org/wikipedia/commons/5/5e/Tape_measure_colored.jpeg http://pixabay.com/p-41335 www.mozaicworks.com 36. Extend your mentoring & training capacity Accelerate learning through communities of practice Grow your functional leaders and top talents http://www.mozaicworks.com adrian.bolboaca@mozaicworks.com @adibolb 37. References http://upload.wikimedia.org/wikipedia/commons/8/84/Stress_Strain_Ductile_Material.png Lufthansa Magazine http://www.nifc.gov/aviation/av_documents/av_helicopters/SafetyBrief.pdf http://pixabay.com/p-41335 http://pixabay.com/p-33364 http://pixabay.com/p-311409 http://pixabay.com/p-296438 http://pixabay.com/p-29503 http://upload.wikimedia.org/wikipedia/commons/thumb/4/44/Official_policy_seal.svg/32 https://www.flickr.com/photos/barrydahl/6675297699 http://pixabay.com/p-155486 http://pixabay.com/p-303113 https://c1.staticflickr.com/9/8067/8163592864_fa4a9ba8ed_z.jpg www.mozaicworks.com