AZ-400 Chapter 1-3

Question 1

What is devops? (3 things)

Answer 1

Collaboration
Continuous Delivery
Breaking Down Silos

Question 2

What is the struggle between op and dev?

Answer 2

Op wants as few changes as possible while dev is rewarded for more changes

Question 3

What is fastlaning?

Answer 3

Adding urgent, unplanned work to the top of the sprint board as Kanban

Question 4

What are the benefits of devops culture? (2 things)

Answer 4

Reduced cycle time (lower change failure rate), increased employee satisfaction

Question 5

What is cycle time?

Answer 5

Time between starting work on a task and the moment a user can use it

Question 6

Metrics for measuring results (4 things)

Answer 6

Cycle Time and Lead Time
Amount of work in progress
Mean time to recovery
Change rate (change failure rate included)

Question 7

What is lead time?

Answer 7

Time between a request for a feature and the user reciving it

Question 8

7 Key DevOps Practices

Answer 8

Config Management
Release Management
CI
CD
Infrastructure as code
Test automation
App Performance Monitoring

Question 9

7 DevOps Habits
Team auto…

Answer 9

Team autonomy
managing technical debt
flow of customer value
hypothesis driven development
evidence gathered in PROD
live-site culture
infrastructure as a resource

Question 10

Where should config files live?

Answer 10

In source control as JSON or YAML. This prevents configuration drift

Question 11

The version and config of a release is stored as?

Answer 11

An artifact

Question 12

What kind of metrics are used for app performance monitoring? (3)

Answer 12

Response time, # of requests, use patterns

Question 13

What are the 5 stages of DevOps evolution?

Answer 13

Normalizing the tech stack
Standardizing and reducing variability
Expand DevOps Practices
Automate infrastructure delivery
Provide self-service capabilities

Question 14

What is SRE?

Answer 14

Site reliability engineering
Goal is to improve stability and reliability
Use automation to reduce repetitive tasks
Should spend 50% of time on Op work, the rest on automation, deployment pipelines and reviewing alerts

Question 15

What is reliability and availability?

Answer 15

Reliability - likelihood of services performing predictably
Availability - percentage of time the system is fully operational

Reliability is a subset of availability

availability % = (uptime seconds - downtime seconds) / uptime *100

Question 16

What things are needed to make service reliable? (7 things)

Answer 16

Monitoring
Incident response (coordinate, communicate, control)
Post Mortem
Testing and Release Procedures
Capacity Planning (scaling and resources)
Development (use active and standby regions to help uptime)
Product

Question 17

What is the difference between SLA, SLO and SLI?

Answer 17

SLA - service license agreement. Legal doc. Uptime is hard here (99.999%)
SLO - derived from business objectives, uptime can be loosely defined here
SLI - service level indicator - a metric to focus on

Question 18

Name 4 key SLI’s

Answer 18

Request latency (time taken to return a response)
availability (fraction of time available)
success rate
throughput (requests per second)

Question 19

What are the 4 key activities in DevOps?

Answer 19

Plan and Track
Develop and Test
Deploy and Release
Monitor and Learn

Question 20

What suites are within Azure DevOps? (5 things)

Answer 20

Azure Boards, Repos, Pipelines, Test Plans, and Artifacts

Question 21

What suites are within Azure Monitor?

Answer 21

Monitor Logs, Monitor Metrics, and App Insights