DevOps and Its Importance Study Notes
DevOps Overview – Covers culture, performance metrics, CI/CD, CALMS model, automation, continuous testing, and frameworks like Agile, SAFe, and SRE. Ideal for modern IT and DevOps foundation learning.
Alice Edwards
Contributor
4.4
50
2 months ago
Preview (22 of 71)
Sign in to access the full document!
1
□ What is DevOps?
o A cultural and professional movement that stresses communication, collaboration, and
integration between software developers and IT operations professionals while
automating the process of software delivery and infrastructure changes. It aims at
establishing a culture and environment where building, testing, and releasing software,
can happen rapidly, frequently, and more reliably.
o "Imagine a world where product owners, Development, QA, IT Operations and Infosec
work together, not only to help each other, but also to ensure that the overall
organization succeeds. By working towards a common goal, they enable the fast flow of
planned work into production, while achieving world-class stability, reliability, availability
and security."
U Why is DevOps Important?
o To meet these changing conditions, culture, practices and automation must become
more "continuous".
U DevOps Performance:
o Highly evolved organizations have consistently demonstrated higher performance across
four key software performance metrics.
o "Organizations that are "good at DevOps" have strong identities, clear responsibilities,
autonomy over their own function, and well-defined interaction paradigms and
communication channels with other teams."
L Development frequency: Low: Monthly or less often. Mid: Between daily and
weekly. High: On demand (whenever we want).
□ Lead time for changes: Low: Between a week and 6 months. Mid: Less than a
week. High: Less than an hour.
□ MTTR: Low: Less than a week. Mid: Less than a day. High: Less than an hour.
L Change failure rate: Low: Less than 15%. Mid: Less than 15%. High: Less than
15%.
□ DevOps Foundation:
o With DevOps, people across the IT organization, working together, enable fast flow,
feedback, and continuous improvement of planned work into production, while
achieving quality, stability, reliability, availability, security, and team satisfaction.
□ Practices: Automation, Architecture, Continuous Integration, Continuous
Delivery/Deployment, Continuous Testing.
□ Culture: Safe, trusting, respectful, collaborative, data driven, continuous
improvement, shared accountabilities.
o The Three Ways: are DevOps patterns identified in both "The DevOps Handbook" as well
as "The Phoenix Project."
□ The first way: Systems thinking.
□ The second way: Amplify Feedback Loops.
□ The third way: Culture of Continual Experimentation and Learning.
1. Continuous Flow
□ What is DevOps?
o A cultural and professional movement that stresses communication, collaboration, and
integration between software developers and IT operations professionals while
automating the process of software delivery and infrastructure changes. It aims at
establishing a culture and environment where building, testing, and releasing software,
can happen rapidly, frequently, and more reliably.
o "Imagine a world where product owners, Development, QA, IT Operations and Infosec
work together, not only to help each other, but also to ensure that the overall
organization succeeds. By working towards a common goal, they enable the fast flow of
planned work into production, while achieving world-class stability, reliability, availability
and security."
U Why is DevOps Important?
o To meet these changing conditions, culture, practices and automation must become
more "continuous".
U DevOps Performance:
o Highly evolved organizations have consistently demonstrated higher performance across
four key software performance metrics.
o "Organizations that are "good at DevOps" have strong identities, clear responsibilities,
autonomy over their own function, and well-defined interaction paradigms and
communication channels with other teams."
L Development frequency: Low: Monthly or less often. Mid: Between daily and
weekly. High: On demand (whenever we want).
□ Lead time for changes: Low: Between a week and 6 months. Mid: Less than a
week. High: Less than an hour.
□ MTTR: Low: Less than a week. Mid: Less than a day. High: Less than an hour.
L Change failure rate: Low: Less than 15%. Mid: Less than 15%. High: Less than
15%.
□ DevOps Foundation:
o With DevOps, people across the IT organization, working together, enable fast flow,
feedback, and continuous improvement of planned work into production, while
achieving quality, stability, reliability, availability, security, and team satisfaction.
□ Practices: Automation, Architecture, Continuous Integration, Continuous
Delivery/Deployment, Continuous Testing.
□ Culture: Safe, trusting, respectful, collaborative, data driven, continuous
improvement, shared accountabilities.
o The Three Ways: are DevOps patterns identified in both "The DevOps Handbook" as well
as "The Phoenix Project."
□ The first way: Systems thinking.
□ The second way: Amplify Feedback Loops.
□ The third way: Culture of Continual Experimentation and Learning.
1. Continuous Flow
2
2. Continuous Feedback
3. Continuous Experiment and Learning
□ Frameworks: Agile and SAFe, Lean, ITSM, DevSecOps, SRE (Site Reliability Engineering), VSM
(Value Stream Management).
□ Values: CALMS (see below)
o CALMS Model:
F Considered the pillars or values of DevOps: Culture, Automation, Lean,
Measurement, Sharing (as put forth by John Willis, Damon Edwards, and Jez
Humble).
□ Continuous Testing:
o Continuous Testing is the process of executing automated tests as part of the pipeline to
obtain immediate feedback on the business risks associated with a software release
candidate. "Shifting left" is about building quality into the software development
process. When you shift left, fewer things break in production, because any issues are
detected and resolved earlier.
Fl Shift Left means:
o An approach that strives to build quality into the software development process by
incorporating testing early and often. This notion extends to security architecture,
hardening images, application security testing, and beyond.
U Continuous Integration (CI)
o A development practice that requires developers to merge their code into trunk or
master ideally at least daily and perform tests (i.e. unit, integration, and acceptance) at
every code commit.
o Continuous integration (CI) is a development practice that requires developers to
commit code into a shared repository (master/trunk) at least daily.
o While mostly associated with agile software development, waterfall approaches can also
take advantage of continuous integration and testing practices.
o Each commit is:
□ Validated by an automated build, automated unit, integration and acceptance
tests.
F Is dependent on consistent coding standards.
L Requires version control repositories and CI servers to collect, build and test
committed code together.
□ Runs on production-like environments.
□ Enables early detection and quick remediation of errors from code changes
before moving to production.
U Continuous Delivery (CD)
o A methodology that focuses on making sure software is always in a releasable state
throughout its lifecycle.
2. Continuous Feedback
3. Continuous Experiment and Learning
□ Frameworks: Agile and SAFe, Lean, ITSM, DevSecOps, SRE (Site Reliability Engineering), VSM
(Value Stream Management).
□ Values: CALMS (see below)
o CALMS Model:
F Considered the pillars or values of DevOps: Culture, Automation, Lean,
Measurement, Sharing (as put forth by John Willis, Damon Edwards, and Jez
Humble).
□ Continuous Testing:
o Continuous Testing is the process of executing automated tests as part of the pipeline to
obtain immediate feedback on the business risks associated with a software release
candidate. "Shifting left" is about building quality into the software development
process. When you shift left, fewer things break in production, because any issues are
detected and resolved earlier.
Fl Shift Left means:
o An approach that strives to build quality into the software development process by
incorporating testing early and often. This notion extends to security architecture,
hardening images, application security testing, and beyond.
U Continuous Integration (CI)
o A development practice that requires developers to merge their code into trunk or
master ideally at least daily and perform tests (i.e. unit, integration, and acceptance) at
every code commit.
o Continuous integration (CI) is a development practice that requires developers to
commit code into a shared repository (master/trunk) at least daily.
o While mostly associated with agile software development, waterfall approaches can also
take advantage of continuous integration and testing practices.
o Each commit is:
□ Validated by an automated build, automated unit, integration and acceptance
tests.
F Is dependent on consistent coding standards.
L Requires version control repositories and CI servers to collect, build and test
committed code together.
□ Runs on production-like environments.
□ Enables early detection and quick remediation of errors from code changes
before moving to production.
U Continuous Delivery (CD)
o A methodology that focuses on making sure software is always in a releasable state
throughout its lifecycle.
3
C Continuous Deployment:
o A set of practices that enable every change that passes automated tests to be
automatically deployed to production.
o Continuous delivery is a methodology that focuses on making sure software is always in
a releasable state throughout its lifecycle.
o Takes continuous integration to next level.
o Provides fast, automated feedback on a system's production-readiness.
o Prioritizes keeping software releasable/deployable over working on new features.
o Relies on deployment pipeline that enables push-button deployments on demand.
o Reduces the cost, time, and risk of delivering incremental changes.
□ Continuous Delivery & Continuous Deployment:
o Continuous delivery is a prerequisite for continuous deployment into production.
□ Continuous Delivery: Dev > Application test > Integration test > Automatic
trigger < Acceptance test > Manual trigger < Production.
□ Continuous Deployment: Dev > Application test > Integration test > Automatic
trigger < Acceptance test > Manual trigger < Production.
□ DevSecOps:
o A mindset that "everyone is responsible for security" with the goal of safely distributing
security decisions at speed and scale to those who hold the highest level of context
without sacrificing the safety required.
o Goal: Safely distributed security decisions at speed and scale.
o Dev: Software. Sec: Safer. Ops: Sooner. "Through Security as Code, we have and will
learn that there is simply a better way for security practitioners, like us, to operate and
contribute value with less friction. We know we must adapt our ways quickly and foster
innovation to ensure data security and privacy issues are not left behind because we
were too slow to change." — 2019 MP Infotech Corp.
o "I believe the DevOps movement is a new fertile soil from which the build-security-in
concept can be reborn, renamed, and remade." Larry Maccherone.
o Values:
□ Build security in more than bolt it on.
C Rely on empowered development teams more than security specialists.
F Implement features securely more than security features.
□ Use tools as feedback for learning more than end-of-phase stage gates.
□ Build on culture change more than policy enforcement.
LI Value Stream Management:
o Value Stream Management is a combination of people, processes, and technologies that
maps, optimizes, visualizes, measures, and governs business value flow through
heterogeneous software delivery pipelines from idea through development and into
production.
C Continuous Deployment:
o A set of practices that enable every change that passes automated tests to be
automatically deployed to production.
o Continuous delivery is a methodology that focuses on making sure software is always in
a releasable state throughout its lifecycle.
o Takes continuous integration to next level.
o Provides fast, automated feedback on a system's production-readiness.
o Prioritizes keeping software releasable/deployable over working on new features.
o Relies on deployment pipeline that enables push-button deployments on demand.
o Reduces the cost, time, and risk of delivering incremental changes.
□ Continuous Delivery & Continuous Deployment:
o Continuous delivery is a prerequisite for continuous deployment into production.
□ Continuous Delivery: Dev > Application test > Integration test > Automatic
trigger < Acceptance test > Manual trigger < Production.
□ Continuous Deployment: Dev > Application test > Integration test > Automatic
trigger < Acceptance test > Manual trigger < Production.
□ DevSecOps:
o A mindset that "everyone is responsible for security" with the goal of safely distributing
security decisions at speed and scale to those who hold the highest level of context
without sacrificing the safety required.
o Goal: Safely distributed security decisions at speed and scale.
o Dev: Software. Sec: Safer. Ops: Sooner. "Through Security as Code, we have and will
learn that there is simply a better way for security practitioners, like us, to operate and
contribute value with less friction. We know we must adapt our ways quickly and foster
innovation to ensure data security and privacy issues are not left behind because we
were too slow to change." — 2019 MP Infotech Corp.
o "I believe the DevOps movement is a new fertile soil from which the build-security-in
concept can be reborn, renamed, and remade." Larry Maccherone.
o Values:
□ Build security in more than bolt it on.
C Rely on empowered development teams more than security specialists.
F Implement features securely more than security features.
□ Use tools as feedback for learning more than end-of-phase stage gates.
□ Build on culture change more than policy enforcement.
LI Value Stream Management:
o Value Stream Management is a combination of people, processes, and technologies that
maps, optimizes, visualizes, measures, and governs business value flow through
heterogeneous software delivery pipelines from idea through development and into
production.
Loading page 6...
Loading page 7...
Loading page 8...
Loading page 9...
Loading page 10...
Loading page 11...
Loading page 12...
Loading page 13...
Loading page 14...
Loading page 15...
Loading page 16...
Loading page 17...
Loading page 18...
Loading page 19...
Loading page 20...
Loading page 21...
Loading page 22...
19 more pages available. Scroll down to load them.
Preview Mode
Sign in to access the full document!
100%
Study Now!
XY-Copilot AI
Unlimited Access
Secure Payment
Instant Access
24/7 Support
Document Chat
Document Details
Subject
Information Technology