Free Practice Questions for PeopleCert DevOps-SRE Exam

Comprehensive and Detailed Explanation From Exact Extract:

Fixed error budgets are preferred in SRE because they encourage smaller, safer, and more predictable releases, which inherently reduces risk. A fixed budget forces the team to consistently evaluate how much reliability they can afford to trade for delivery speed each month or quarter.

From the Site Reliability Engineering Book, Chapter “Service Level Objectives”:

“Error budgets allow teams to make controlled decisions about the risk they take on. A fixed budget naturally encourages teams to release in smaller batches, which reduces the overall risk and impact of a failure.”

Similarly, the SRE Workbook states:

“When teams work within a fixed error budget, they tend to push changes in smaller increments to avoid burning the budget too quickly.”

Why the other options are incorrect:

A Fixed budgets reduce toil by reducing firefighting, not increase it.

C Fixed budgets can be exceeded; this is not a reason they are beneficial.

D Error budgets do not predict outages; they measure tolerated unreliability.

Thus, the correct and SRE-supported answer is B.

Comprehensive and Detailed Explanation From Exact Extract:

SRE and DevOps release engineering define a canary release as rolling out new features to a small subset of users to validate reliability and performance before full release. The SRE Book states: “Canarying is the practice of releasing changes to a small percentage of users or servers first to detect issues before global rollout.” This minimizes risk by catching regressions early without impacting the entire user base.

Option B fits this definition exactly.

Option A (rolling wave) is a deployment pattern but not canarying.

Option C resembles phased rollout but not specifically canary release.

Option D describes testing, not production canary deployment.

Thus, B is correct.

Comprehensive and Detailed Explanation From Exact Extract:

SRE is built on transparency and broad information sharing. The SRE Book states: “High-quality operations require that information flows freely between product development, SRE, and associated teams.” (SRE Book – Chapter: Communication and Collaboration). Effective incident management also depends on complete data availability: “Centralized, shared information reduces cognitive load and improves incident resolution.” (SRE Workbook – Incident Management).

Option B aligns perfectly with SRE principles: data must flow freely, ensuring everyone has access to metrics, logs, architecture details, incident context, and SLOs.

Options A, C, and D promote restricted or fragmented data practices, which are directly contrary to SRE design. SRE teams avoid information silos.

Thus, B is correct.

Comprehensive and Detailed Explanation From Exact Extract:

Traditional monitoring works well when systems are static and predictable. However, cloud-native, distributed, and microservice-based architectures create highly dynamic environments. In these cases, observability becomes more effective because it provides visibility across entire systems, rather than focusing on individual components.

From Google’s Observability guidance:

“Traditional monitoring relies on predefined dashboards and known failure modes. In modern cloud systems, component-level monitoring becomes insufficient because failures occur in ways that cannot always be predicted.”

Further, in the SRE Workbook:

“Monitoring individual components does not provide adequate visibility into complex distributed systems. Observability enables teams to understand system-wide behavior and user impact.”

Why options are incorrect:

A Observability is not inherently cheaper.

C While true, it is not the best reason; observability's benefit is broader than scale alone.

D Traditional monitoring can support containers but often becomes noisy and ineffective.

Thus, the best answer is B.

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:

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:

A Network Reliability Engineer (NRE) is a specialized reliability role focused on applying SRE practices to networking. They use software engineering, SDLC concepts, and automation to manage networks at scale, including SDNs.

Google describes NRE as:

“Network Reliability Engineering applies SRE principles to network management, treating network configuration as code and automating changes safely.”

— Google Reliability Engineering Guidance

Responsibilities include:

Codifying SDN configurations

Automating network deployment

Testing network changes through CI/CD

Reducing network-related outages

Thus, the correct answer is B.

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.

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:

The SRE Book defines reliability as: “the probability that a system will perform its intended function correctly for a specified period of time.” (SRE Book – Introduction). Reliability focuses on correctness and consistent performance, not simply uptime. Availability (option A) refers to system uptime or accessibility. Durability (option C) refers to long-term data persistence. Throughput (option D) measures volume of work processed over time.

Because the definition explicitly mentions probability of meeting performance standards and correct output over time, it directly matches the SRE definition of reliability.

Thus, B is correct.