PracHub
QuestionsPremiumLearningGuidesCheatsheetNEWCoaches
|Home/Software Engineering Fundamentals/Google

Explain SLI/SLO/SLA and design monitoring

Last updated: Mar 29, 2026

Quick Overview

This question evaluates a candidate's competency in service reliability and observability, specifically understanding and distinguishing SLIs, SLOs, and SLAs, planning error budgets, and designing monitoring and alerting for a production web API.

  • hard
  • Google
  • Software Engineering Fundamentals
  • Software Engineer

Explain SLI/SLO/SLA and design monitoring

Company: Google

Role: Software Engineer

Category: Software Engineering Fundamentals

Difficulty: hard

Interview Round: Onsite

Explain the differences between SLI, SLO, and SLA with concrete examples for a web API (e.g., availability and latency). Given a quarterly target SLO, define a reasonable error budget and show how you would apportion and track its consumption over time. Then design a monitoring and alerting system that minimizes alert fatigue: choose which signals to alert on, set thresholds relative to SLOs, aggregate and deduplicate alerts, apply multi-window/multi-burn-rate policies, and define escalation, silencing, and runbook practices.

Quick Answer: This question evaluates a candidate's competency in service reliability and observability, specifically understanding and distinguishing SLIs, SLOs, and SLAs, planning error budgets, and designing monitoring and alerting for a production web API.

Related Interview Questions

  • Process Sharded Login Logs - Google (medium)
  • Design an ads retrieval service using a heap - Google (easy)
  • Design a waitlist manager - Google (easy)
  • Design an editable sequence with marker - Google (medium)
  • Design a waitlist system with top/bottom K - Google (medium)
Google logo
Google
Sep 6, 2025, 12:00 AM
Software Engineer
Onsite
Software Engineering Fundamentals
3
0

SLI vs SLO vs SLA for a Web API; Error Budgets; Monitoring and Alerting Design

Context: You are designing reliability goals and on-call policies for a production web API that serves JSON over HTTPS. Requests include a mix of GET/POST endpoints. You need to define what you measure (SLIs), targets (SLOs), the contractual promise (SLA), plan an error budget for a quarterly SLO, and design monitoring/alerting that minimizes alert fatigue.

Tasks

  1. Define and contrast SLI, SLO, and SLA. Give concrete SLI examples for:
    • Availability (success rate)
    • Latency (e.g., request duration under a threshold)
  2. Given a quarterly target SLO, define a reasonable error budget, and show how you would apportion and track its consumption over time.
  3. Design a monitoring and alerting system that minimizes alert fatigue:
    • Choose which signals to alert on and why
    • Set alert thresholds relative to SLOs
    • Aggregate and deduplicate alerts
    • Apply multi-window/multi-burn-rate policies
    • Define escalation, silencing, and runbook practices

Solution

Show

Comments (0)

Sign in to leave a comment

Loading comments...

Browse More Questions

More Software Engineering Fundamentals•More Google•More Software Engineer•Google Software Engineer•Google Software Engineering Fundamentals•Software Engineer Software Engineering Fundamentals
PracHub

Master your tech interviews with 7,500+ real questions from top companies.

Product

  • Questions
  • Learning Tracks
  • Interview Guides
  • Resources
  • Premium
  • For Universities
  • Student Access

Browse

  • By Company
  • By Role
  • By Category
  • Topic Hubs
  • SQL Questions
  • Compare Platforms
  • Discord Community

Support

  • support@prachub.com
  • (916) 541-4762

Legal

  • Privacy Policy
  • Terms of Service
  • About Us

© 2026 PracHub. All rights reserved.