Site Reliability Engineering Flashcards

What is Site Reliability Engineering (SRE)?

Answer: A discipline that applies software engineering principles to operations to create scalable, reliable systems

SRE, originated at Google, treats operations as a software engineering problem, using code and automation to manage production systems and maintain reliability.

What is an SLA (Service Level Agreement)?

Answer: A formal contract with customers defining minimum service quality and remedies for failures

An SLA is a legally binding commitment to customers specifying uptime, performance, and support response standards with financial penalties for breaches.

What is 'toil' in SRE terminology?

Answer: Manual, repetitive operational work that is automatable, tactical, and scales with service growth

SRE defines toil as work that is manual, repetitive, automatable, tactical, and grows proportionally with service load — teams aim to keep toil below 50% of work time.

What is chaos engineering?

Answer: Deliberately injecting failures into a system to test its resilience and identify weaknesses before they cause incidents

Chaos engineering (e.g., Netflix's Chaos Monkey) proactively breaks things in controlled ways to discover failure modes and verify that systems handle them gracefully.

What is an incident post-mortem?

Answer: A blameless analysis after an incident to understand root causes and prevent recurrence

A blameless post-mortem focuses on systemic causes rather than individual blame, documenting the timeline, contributing factors, and action items to prevent recurrence.

What does 'capacity planning' mean in SRE?

Answer: Forecasting future resource needs and provisioning infrastructure ahead of demand

Capacity planning uses growth projections and load models to ensure infrastructure can handle future traffic before it arrives, avoiding reactive scaling crises.