DevOps-SRE Site Reliability Engineering (SRE) Foundation v1.2 Questions and Answers

Comprehensive and Detailed Explanation From Exact Extract:

Containers provide a major advantage that aligns with SRE: portability and environment consistency. The SRE Workbook describes containers as: “lightweight, portable units that encapsulate applications and dependencies, ensuring consistent behavior across environments.” This independence from the host OS environment enables predictable deployments and simplifies automation, scaling, and orchestration—especially when used with Kubernetes.

Option A captures this exact benefit: portability and independence from the host OS.

Option B is incorrect—containers do not reduce the number of developers required.

Option C incorrectly claims that efficiency comes from virtual machines; containers are typically more efficient because they avoid VM overhead, not leverage it.

Option D is incorrect—containers do not “inherit” security automatically; in fact, they require additional security controls.

Thus, A is the correct answer.

Comprehensive and Detailed Explanation From Exact Extract:

Modern SRE-aligned organizations use small, cross-functional product teams capable of owning design, development, testing, and operational reliability. The SRE Book emphasizes: “Effective service ownership arises from small, autonomous teams with diverse skillsets and strong collaboration habits.” These teams share responsibility, encourage feedback, and maintain open communication to meet reliability goals.

Option A correctly identifies the two positive characteristics:

Small and collaborative

Cross-functional skillsets

Options 3 and 4 represent dysfunctional behaviors—SRE literature explicitly discourages responsibility silos and discouraging feedback, as these reduce reliability and slow incident learning.

Thus, A is the correct answer.

Comprehensive and Detailed Explanation From Exact Extract:

The foundational definition of SRE, as stated in Google’s SRE Book, is that SRE uses software engineering as its primary tool to solve operational problems: “SRE is fundamentally doing operations work using software engineering approaches.” (SRE Book – What Is SRE?). This includes building automation, writing tools, creating pipelines, and eliminating manual work. The “engineering side” focuses specifically on applying coding practices, testing, CI/CD, version control, and automation frameworks to operational domains such as deployment, monitoring, incident response, and capacity planning.

Option D captures this precisely: using software engineering best practices to solve operational issues and drive automation.

Options A, B, and C focus too narrowly on network or infrastructure engineering. While these can be components of SRE, they do not describe its engineering foundation as Google defines it.

Thus, D is the correct answer.

Comprehensive and Detailed Explanation From Exact Extract:

A Production Readiness Review (PRR) is a core SRE practice ensuring that a service meets specific reliability, operational, monitoring, and alerting standards before SRE assumes responsibility. The Site Reliability Engineering (SRE) Workbook states: “PRRs validate that a service is prepared for production and ready for SRE engagement, ensuring operational readiness, monitoring completeness, on-call preparation, and automation maturity.” The goal is not merely organizational handover but ensuring the service is fully prepared for reliable operation in production.

Option A fits this definition exactly: ensuring the service is ready for SRE support.

Option B focuses on development/testing readiness, not production readiness.

Option C references standards/frameworks not part of PRR’s purpose.

Option D is only a partial implication—transition of accountability happens after PRR readiness, not the main purpose of PRR.

Thus, A is the correct SRE-aligned answer.

Comprehensive and Detailed Explanation From Exact Extract:

Application Performance Management (APM) refers to a set of tools and practices used to monitor and manage the performance, behavior, and availability of software applications. Although APM is not defined exclusively in the Google SRE Book, it is described within the broader context of monitoring and observability.

In the SRE Workbook, under Monitoring:

“Application monitoring tools provide insights into the performance, latency, availability, and behavior of applications to help engineering teams maintain reliability.”

Industry-standard APM frameworks (including Google Cloud Operations Suite, formerly Stackdriver) define APM as:

“The monitoring and management of application performance and availability.”

Why the other options are incorrect:

A describes telemetry, not APM.

C describes system monitoring (infrastructure), not application performance monitoring.

D refers to communication of metrics, not the monitoring of application performance.

Therefore, B is the correct definition.

Comprehensive and Detailed Explanation From Exact Extract:

The future growth envelope refers to the anticipated growth trajectory of a service, including expected load, user demand, data volume, and performance requirements. Planning for this growth is essential to ensuring that a service can scale reliably without violating SLOs.

The Site Reliability Engineering Book, in discussions on capacity planning, states:

“A key element of capacity planning is estimating future demand so that systems can scale to meet user needs without sacrificing reliability.”

The SRE Workbook reinforces this concept:

“Understanding expected growth enables teams to design systems that scale and remain reliable as usage increases.”

Having the growth envelope defined enables:

Proper capacity planning

Avoiding resource exhaustion

Ensuring scalability before it becomes a reliability problem

Designing architectures that can handle future load

Why the other options are incorrect:

A Signed artifacts relate to supply chain security, not scaling.

C SLO/SLI reviews do not require growth envelope analysis.

D Error budgets relate to reliability thresholds, not capacity forecasting.

Thus, B is the correct answer.

Comprehensive and Detailed Explanation From Exact Extract:

One of the central goals of SRE is that operational work must scale sublinearly with service growth. The SRE Book states: “If operational load grows linearly with service size, the model is unsustainable. Eliminating toil is key to scaling operations.” (SRE Book – Chapter: Eliminating Toil). Toil prevents scaling because it is manual, repetitive, and tied directly to human effort.

Option C is the only answer that reflects this principle: reducing or eliminating toil enables SRE teams to support growing applications without increasing human labor proportionally.

Option A (staffing levels) does not scale sustainably.

Option B (interruptions) relate to productivity but not true scalability.

Option D (on-call rotations) affects fatigue, not the scaling of operational work.

Thus, C is the correct and SRE-authentic answer.

Comprehensive and Detailed Explanation From Exact Extract:

SRE emphasizes organizational alignment and collaboration, warning against siloed thinking. The SRE Book highlights: “Local optimizations at the expense of the broader system lead to inefficiency, misalignment, and reduced reliability.” When individuals or teams focus only on their own “parts” instead of shared goals (“the whole”), it results in decreased cross-team communication, isolation, operational friction, and reduced efficiency.

Option B captures this SRE-documented outcome: increased introversion (siloing) and decreased efficiency.

Option A and D describe positive outcomes that contradict SRE principles of collaboration.

Option C implies healthy sharing, which does not result from silo-first behavior.

Thus, B is correct.

Comprehensive and Detailed Explanation From Exact Extract:

Google’s SRE approach emphasizes a blameless postmortem culture as a core learning mechanism. After a major outage, SRE teams conduct structured analyses to understand the root causes, contributing factors, and systemic weaknesses. The SRE Book defines this culture explicitly: “Postmortems are written analyses following incidents, designed to capture what happened, why it happened, and how to prevent the issue from recurring.” (SRE Book – Chapter: Postmortem Culture). This learning-focused approach reduces blame, increases resilience, and improves future reliability.

Option C aligns exactly with this principle.

Option A (follow-up culture) is vague and not an SRE term.

Option B (major incident culture) refers to incident handling, not learning afterward.

Option D (problem culture) is unrelated to SRE’s structured post-incident learning.

Thus, C is correct.

Comprehensive and Detailed Explanation From Exact Extract:

Google defines SRE as “what happens when you ask a software engineer to design an operations function.” (SRE Book – Introduction). The core engineering approach in SRE focuses on:

Eliminating toil

Building scalable systems

Applying software engineering to operational challenges

Learning from previous solutions and patterns

The SRE Book emphasizes: “SREs focus on designing and engineering solutions that reduce manual operations and scale service delivery.” (Chapter: Eliminating Toil). This aligns directly with Option B: designing a solution to eliminate toil and scale service delivery, informed by prior successful engineering patterns.

Option A focuses only on automating a single tuning activity—not holistic engineering.

Option C describes deployment, not engineering approach to operations.

Option D is about incident response, not engineering strategy.

Thus, B is the best representation of SRE’s engineering approach.

Comprehensive and Detailed Explanation From Exact Extract:

A blameless post-mortem is a foundational SRE practice that encourages truthful, detailed reporting after an incident. The purpose is to learn, not punish. Google SRE emphasizes that engineers must feel psychologically safe to report what they did, what they assumed, and why they made those decisions.

From the Site Reliability Engineering Book, Chapter “Postmortem Culture”:

“Blameless postmortems encourage engineers to share the full details of their actions and assumptions without fear of punishment, enabling learning and preventing repeated failures.”

The book further states:

“Understanding the assumptions made during an incident is critical to uncovering systemic issues.”

Thus:

Engineers must report without fear of retribution

They must report assumptions and decisions made during the incident

Therefore, the correct answer is C. Both A and B.

Why the other options are insufficient:

A Only partially correct

B Only partially correct

D Testing data may be included, but it is not the defining feature of blameless postmortems

Comprehensive and Detailed Explanation From Exact Extract:

The goal of Site Reliability Engineering (SRE) is to create ultra-scalable and highly reliable distributed software systems. This principle is clearly articulated in the foundational text of SRE, the Google Site Reliability Engineering book.

From Chapter 1: Introduction of the Site Reliability Engineering book:

"SRE is what happens when you ask a software engineer to design an operations team. Our approach to service management is rooted in our belief that engineering work to create scalable and highly reliable systems is critical to the success of modern software."

— Site Reliability Engineering Book, Chapter 1

This statement establishes that building and maintaining scalable, reliable systems is the core mission of SRE. While concepts like reducing toil (option A), implementing SLOs (option B), and aligning with DevOps (option C) are vital components of the SRE practice, they support the overarching goal — which is option D.

Therefore, the correct answer is D: To create ultra-scalable and highly reliable distributed software systems.

Comprehensive and Detailed Explanation From Exact Extract:

Embracing failure—through practices such as blameless postmortems, chaos engineering, and proactive detection—enables organizations to improve their incident response performance. This directly improves:

MTTD (Mean Time to Detect)

MTTR (Mean Time to Recover)

The Site Reliability Engineering Book, chapter “Postmortem Culture,” states:

“By examining failures without blame and learning from them, organizations improve their ability to detect issues faster and recover more quickly.”

Similarly, in the SRE Workbook, section on incident response:

“Learning from incidents is essential to reducing time to detection and time to mitigation.”

Why the other options are incorrect:

A MTBSI (Mean Time Between System Incidents) is influenced by architecture and testing, not directly by embracing failure.

B These are DORA metrics — important, but not primarily tied to failure-embracing practices.

C Too vague and not a standard SRE metric pair.

Thus, D is the correct answer.

Comprehensive and Detailed Explanation From Exact Extract:

In a safety culture, SRE emphasizes psychological safety so engineers can work effectively in production without fear of blame. However, safety never removes accountability. Engineers must take responsibility for their actions, decisions, and assumptions, particularly during incidents.

The Site Reliability Engineering Book, Chapter “Postmortem Culture,” states:

“Blamelessness does not eliminate accountability. Individuals must still explain the context, assumptions, and reasoning behind their decisions so that the organization can learn.”

Google stresses that:

Engineers must feel safe to act and report issues

Engineers must remain responsible and accountable

Accountability enables learning, not punishment

Why other options are incorrect:

A Sharing incidents on social media violates confidentiality

C Blameless postmortems are required, not skipped

D Avoiding on-call is contrary to SRE responsibilities

Thus, B is correct.

Comprehensive and Detailed Explanation From Exact Extract:

The term “wisdom of production” refers to the insights gained from real systems running under actual production conditions. Only production environments exhibit real user behavior, real workloads, true performance characteristics, and authentic failure modes. This concept is rooted in the SRE philosophy that production is the ultimate source of truth for understanding system behavior.

From the SRE Workbook, Chapter “Monitoring”:

“Only production provides the full truth about how a system behaves under real workloads. Production is the ultimate source of wisdom about the system.”

This makes clear that wisdom gained from production is indispensable. Testing and staging environments cannot reproduce all real-world variables, usage patterns, and failure pathways.

Why the other options are incorrect:

A describes engineering approaches but does not define “wisdom of production.”

C is incorrect because staging environments do not provide production wisdom.

D relates to automation strategy, not production insights.

Thus, the accurate meaning of the term is B — The wisdom gained from something running in production.

Comprehensive and Detailed Explanation From Exact Extract:

SRE defines effective monitoring as comprehensive observability across all layers of a system, including latency, traffic, errors, saturation, dependencies, and infrastructure. The SRE Book states: “Monitoring must offer insight across all system components, enabling teams to rapidly detect and diagnose issues.” (SRE Book – Monitoring Distributed Systems). Observability instrumentation (logs, metrics, traces) provides the necessary depth for reliable digital experience monitoring.

Option B captures this exactly: broad observability across all components and layers.

Option A rejects modern observability practices—contradicting SRE guidance.

Option C is too narrow (network-only).

Option D focuses only on advanced technologies, not comprehensive coverage.

Thus, B is the best answer.

Comprehensive and Detailed Explanation From Exact Extract:

The primary difference between SRE and DevOps lies in their implementation focus and origins, though they share similar objectives. According to Google’s official SRE documentation:

“SRE can be seen as a specific implementation of DevOps with some idiosyncratic extensions.”

— Site Reliability Engineering Book, Chapter: What is Site Reliability Engineering?

While DevOps is a broad cultural and organizational philosophy aimed at closing the gap between development and operations through collaboration and automation, SRE provides a concrete, engineering-driven approach to achieving those goals — particularly through practices like error budgets, SLIs/SLOs, toil reduction, and incident response.

SRE focuses heavily on the post-production lifecycle — including reliability, monitoring, capacity planning, and incident response — whereas DevOps includes these concerns but emphasizes the entire software delivery lifecycle. Hence, Option A is the correct and most accurate answer.

Options B and C are incorrect:

B wrongly implies a division of roles (DevOps = developers, SRE = infrastructure), which is not how these frameworks operate.

C misrepresents SRE — it does not build silos but instead emphasizes shared responsibility and transparency in production systems.

D is incorrect because, while aligned, SRE and DevOps are not identical.

Comprehensive and Detailed Explanation From Exact Extract:

Error budgets are a fundamental SRE mechanism for balancing reliability and innovation. The SRE book states: “The error budget directly governs the rate of change: as long as the service stays within budget, development velocity can remain high.” (SRE Book – Chapter: Service Level Objectives). This means teams can push changes aggressively as long as the allowed amount of unreliability has not been consumed.

The error budget acts as a safety threshold. When reliability dips and the error budget is consumed, SRE enforces a change freeze to restore stability. Google explains: “If the error budget is spent, releases are halted and efforts focus on improving reliability.” Feature velocity is not arbitrarily slowed—it is governed solely by the remaining error budget.

Option A best expresses this: when the error budget is high, teams can safely accelerate feature delivery.

Option D incorrectly suggests rushing, which contradicts controlled release practices.

Option B misinterprets error budgets as a percentage-based throttling system.

Option C incorrectly implies that innovation stops entirely only when empty.

Thus, A is the correct interpretation according to official SRE principles.

Comprehensive and Detailed Explanation From Exact Extract:

Anti-fragility focuses on an organization’s ability to respond, adapt, learn, and recover from incidents. The most useful metrics relate to incident detection, response, reliability, and recovery. Deployment frequency, while important in DevOps and DORA metrics, does not directly measure anti-fragility.

From the SRE Workbook, Incident Response section:

“Improving antifragility requires better detection, better recovery mechanisms, and clear reliability goals.”

Key metrics relevant to anti-fragility:

MTTD (Mean Time To Detect) — quicker detection improves resilience

MTTR/RPO — recoverability measures

SLOs — define acceptable reliability thresholds and guide learning

Deployment frequency primarily measures delivery velocity, not resilience.

The Site Reliability Engineering Book emphasizes:

“Antifragility is improved by learning from incidents and strengthening recovery mechanisms rather than by increasing release cadence.”

Why other options are correct for anti-fragility:

A. Mean Time To Detect — critical for detecting failures quickly

B. SLOs — define boundaries for reliability and failure tolerance

D. Recovery Point Objective — measures potential loss during failures

Thus, C is the least useful metric for improving antifragility.

Comprehensive and Detailed Explanation From Exact Extract:

Defense-in-Depth (DiD) is a layered security strategy referenced in SRE’s discussions of secure infrastructure and resilience. The perimeter layer is responsible for controlling and monitoring traffic flowing into and out of the network from external sources, such as the public Internet. This includes firewalls, intrusion detection systems, load balancers, and boundary network controls.

While SRE focuses primarily on reliability, the SRE Book stresses the importance of resilient system boundaries: “Perimeter protections are critical where external traffic enters the system.” (SRE Book – Security and Infrastructure considerations).

Option C correctly identifies the Perimeter Layer as the network boundary where data flows in/out from other networks—including the Internet.

Option A (Host layer) secures individual machines.

Option B (Physical layer) refers to hardware, power, racks, etc.

Option D (Data layer) protects stored data, not ingress/egress traffic.

Thus, C is correct.

Comprehensive and Detailed Explanation From Exact Extract:

When a team exceeds its error budget, SRE practice requires applying error budget policies that restrict feature releases and shift focus toward reliability improvement. The idea is to prevent further degradation of user experience and ensure the service meets the agreed reliability targets.

The Site Reliability Engineering Book, Chapter “Service Level Objectives,” states:

“If the service exceeds its error budget, all new feature launches or risky changes are halted until reliability returns to acceptable levels. Engineering work should be directed toward addressing the causes of the budget overrun.”

This aligns with option A, which describes a reliability-focused response during sprint planning. Limiting sprint planning to post-mortem action items and reliability improvements is a direct application of error budget policies.

Additional guidance from the SRE Workbook:

“Error budget burn should directly influence decision-making. When the budget is exhausted, the team must focus on remediation work rather than new features.”

Why the other options are incorrect:

B Reviewing the error budget’s realism can be done periodically, but it is not the immediate consequence of a breach.

C Extending the error budget invalidates its purpose and is discouraged.

D Ignoring the error budget contradicts the entire SRE model and Google’s official guidance.

Therefore, A is the only correct answer.