Why continuous delivery needs devops, and why devops needs infrastructure-as-code Sriram Narayan @sriramnarayan 25-Oct-2012
about me Part of ThoughtWorks Studios Go team Have consulted as Tech Principal, Agile Coach, organization development coach Been a manager, leadership development coach and innovation facilitator Written production code in Java, C#, Ruby and Python 2010 2012
About ThoughtWorks Studios Training on agile foundations, project management, testing, continuous delivery www.thoughtworks-studios.com/services/agile-workshops
Radar and Anthology
Executive summary Why does CD need devops? Because you can t have CD with a siloed org devops helps blur the strict boundary between dev and ops. Why does devops need IaC? IaC helps create a common currency between dev and ops Helps skills crossover
definitions
Continuous delivery is an approach to delivering software that reduces the cost, time, and risk of delivering incremental changes to users. I think of it as agile software delivery/release instead of agile software development ThoughtWorks Anthology, March 2008
1. Your software is releasable throughout its lifecycle
2. Your team prioritizes keeping the software releasable over working on new features
3. Anybody can get fast, automated feedback on the production readiness of your systems any time somebody makes a change to them
4. You can perform push-button releases of any version of the software on demand.
It is a high bar And it isn t easy
devops theagileadmin.com/what-is-devops/ system administrators participating in an agile development process alongside developers and using a many of the same agile techniques for their systems work wikipedia a response to the interdependence of software development and IT operations. It aims to help an organization rapidly produce software products and services.
Q. Why does CD need devops? A. Because you can t have CD with a siloed org and devops helps blur the strict boundary between dev and ops.
http://www.ediblegeography.com/wp-content/uploads/2012/09/steel-silo-460.jpg A typical setup (pre-devops)
http://www.ediblegeography.com/wp-content/uploads/2012/09/steel-silo-460.jpg A typical anti-pattern (post-devops)
Silo trouble What is a silo? Why are silos bad for CD? What causes silos? Understand the causes so that we can take preventive measures
What is a silo? http://wiki.answers.com/q/what_are_organizational_silos Organizational silos are (often) dysfunctional units or departments within an enterprise, characterized by their tendency to protect themselves...they are sometimes the result of unchecked "empire building" by middle management. A less harsh attempt Anything that tends to localize a (technical) competency and create handoffs in a delivery value stream.
Why are silos bad for CD? Silos mean handoffs Handoffs Cannot be continuous or real-time Communication protocol (e.g. SPOC, minutes) Work queues, turn around times, follow ups, priority escalations Can only work with large batch size But...
We all want shorter cycle times This requires small batch size Handoffs double when batch size halves Too much communication overhead Just not responsive enough Ergo, we reduce hand-offs by tearing down silos
Things that promote a silo Org structure, reporting hierarchy Geographic separation Speciality tools Limited licenses to go around e.g. salesforce accounts, expensive deployment tools Speciality teams
Towards autonomous cross-functional teams 7 silos 5 silos no silos ARCHITECTURE ARCHITECTURE DEVELOPMENT BUILD DATABASE TESTING DATABASE OPERATIONS OPERATIONS MAINTENANCE MAINTENANCE 3 cross-functional teams 1. Extreme case: dev team has no people from other functions (7 silos) 2. Many orgs now merge development, build and testing into one team (5 silos) 3. devops tries to merge operations into what then becomes the IT team
Silo mitigation team and org design Organize along business outcomes Create semi-autonomous teams that own outcomes and minimize geographic separation Distribute specialists among the teams rather than create a speciality team Responsiveness over Efficiency It s ok if specialist utilization falls Generalizing specialist, T-shaped people
Silo mitigation choice of tools Use tools & techniques that blur boundaries between specialists rather than define them Same source code repo for app, build and deploy Same wiki tool, work management tool One over-arching tool for the entire continuous delivery value stream Instead of different tools for CI and deployment
http://www.thoughtworks.com/radar Oct 22, 2012
Q. Why does devops need infrastructure-as-code? A. To create a common currency between dev and ops, which in turn helps mutual transfer of skills and insights
infrastructure-as-code Infrastructure described via code Server and network config, base builds, packages, environments, services and config files A domain model for infrastructure First class infrastructure primitives that allow for a declarative description of desired state The phoenix test Bare metal, infrastructure code and data backup
The radar on infrastructure-as-code July 2011 Oct 2012 March 2012
domain model http://wiki.opscode.com/display/chef/chef+concepts+as+uml
IaC samples Chef: data bag Chef: resources in a recipe Chef: scripting a master-slave config From Bryan Beery http://faodata.blogspot.in/2012/04/chef-testimonial-data.html
Application code Common currency Infrastructure code
The power of text Text lends itself better to collaboration and automation Non-proprietary version control, diff and merge So much tooling is available Code and config in the form of text descriptors makes transactions between specialists more fluid.
IaC facilitated crossover What devs learn from ops Resilience Cloud, Virtualization Data centres Inventory Backups & Audits Monitoring What ops learn from devs Domain modelling Common vocabulary Continuous integration Everything in version control DRY Automated testing
Putting it all together source, tests App Source pipeline trigger target nodes build and unit test acceptance deploy-qa publish artifacts pkg repo deploy-production recipes etc Infra Code binaries deploy-performance
continuous delivery devops iterative, not a linear flow from left to right discover analyze validate one cross-functional team of generalizing specialists architect design develop build App dev test acceptance performance exploratory provision inventory audit deploy upgrade rollback Infrastructure-as-code monitor backup text descriptors in version control One tool for traceability, orchestration, visualization
Thank you Please use the Q&A box for questions or comments