DevOps Interview Questions and Answers
1. What is DevOps?
DevOps is a culture that combines development and operations to deliver software faster and reliably.
2. What are DevOps principles?
CI/CD, automation, monitoring, collaboration, and Infrastructure as Code.
3. What is CI?
Continuous Integration means merging code frequently and running automated tests.
4. What is CD?
Continuous Delivery/Deployment automatically releases code to environments.
5. Difference between Delivery and Deployment?
Delivery needs manual approval, Deployment is fully automatic.
6. What is Jenkins?
Jenkins is an automation server used for CI/CD pipelines.
7. What is a pipeline?
A set of automated steps like build, test and deploy.
8. What is Git?
Git is a version control system.
9. What is Docker?
Docker is a containerization tool to package applications.
10. Difference between VM and Docker?
VM has full OS, Docker shares host OS and is lightweight.
11. What is Kubernetes?
Kubernetes manages container deployment and scaling.
12. What is Pod?
Smallest unit in Kubernetes containing containers.
13. What is Deployment?
Manages replicas and updates of pods.
14. What is Service?
Exposes pods to network traffic.
15. What is HPA?
Horizontal Pod Autoscaler scales pods automatically.
16. What is Terraform?
Infrastructure as Code tool for provisioning resources.
17. What is Ansible?
Configuration management and automation tool.
18. Difference between Terraform and Ansible?
Terraform creates infra, Ansible configures it.
19. What is IaC?
Managing infrastructure using code.
20. What is Helm?
Package manager for Kubernetes.
21. What is Blue-Green deployment?
Two environments, switch traffic to new version.
22. What is Canary deployment?
Release to small group first.
23. What is Monitoring?
Tracking system and application health.
24. What is Prometheus?
Metrics monitoring tool.
25. What is Grafana?
Visualization dashboard for metrics.
26. What is ELK stack?
Elasticsearch, Logstash, Kibana for logs.
27. What is Load Balancer?
Distributes traffic across servers.
28. What is AWS EC2?
Virtual server in AWS.
29. What is S3?
Object storage in AWS.
30. What is IAM?
Identity and access management.
31. What is Dockerfile?
Instructions to build Docker image.
32. What is Image?
Template to create container.
33. What is Container?
Running instance of image.
34. What is Registry?
Stores Docker images.
35. What is DevSecOps?
DevOps with integrated security.
36. What is Vault?
Tool for managing secrets.
37. What is Rolling update?
Update pods without downtime.
38. What is DaemonSet?
Runs pod on every node.
39. What is StatefulSet?
Manages stateful apps like DB.
40. What is Namespace?
Logical separation in Kubernetes.
41. What is Nginx?
Web server and reverse proxy.
42. What is Apache?
Popular web server.
43. What is Reverse Proxy?
Server that forwards client requests.
44. What is Scaling?
Increasing or decreasing resources.
45. Vertical vs Horizontal scaling?
Vertical adds power, Horizontal adds servers.
46. What is SLA?
Service Level Agreement.
47. What is SRE?
Site Reliability Engineering.
48. What is Chaos Engineering?
Breaking system to test reliability.
49. What is Webhook?
Triggers actions on events.
50. What is YAML?
Configuration file format.
51. What is GitHub?
Git repository hosting service.
52. What is GitLab?
Repo with built-in CI/CD.
53. What is Bitbucket?
Code hosting platform.
54. What is Artifact?
Build output file.
55. What is Nexus?
Artifact repository.
56. What is SonarQube?
Code quality tool.
57. What is Test Automation?
Automated testing of code.
58. What is Pipeline as Code?
Pipeline defined in file.
59. What is Cron job?
Scheduled task in Linux.
60. What is Shell script?
Automation using Linux commands.
61. What is Linux?
Open-source operating system.
62. What is Ubuntu?
Linux distribution.
63. What is RHEL?
Red Hat Enterprise Linux.
64. What is SSH?
Secure remote login.
65. What is Firewall?
Network security system.
66. What is Port?
Communication endpoint.
67. What is DNS?
Converts domain to IP.
68. What is CDN?
Content delivery network.
69. What is Latency?
Response time delay.
70. What is Throughput?
Requests per second.
71. What is Backup?
Copy of data.
72. What is Disaster Recovery?
Restoring after failure.
73. What is High Availability?
System always running.
74. What is Failover?
Switch to backup system.
75. What is Hotfix?
Urgent bug fix.
76. What is Patch?
Bug or security fix.
77. What is Versioning?
Tracking releases.
78. What is Tagging?
Labeling versions.
79. What is Log?
System event record.
80. What is Audit?
Tracking changes.
81. What is API?
Interface between systems.
82. What is REST?
Stateless API style.
83. What is JSON?
Data exchange format.
84. What is YAML used for?
Kubernetes and CI config.
85. What is Load testing?
Testing heavy traffic.
86. What is Stress testing?
Testing system limits.
87. What is Smoke testing?
Basic functionality check.
88. What is Regression testing?
Checking old features.
89. What is SLA breach?
Service not meeting agreement.
90. What is Incident?
Unexpected issue.
91. What is RCA?
Root cause analysis.
92. What is MTTR?
Mean time to recovery.
93. What is MTBF?
Mean time between failures.
94. What is Uptime?
System availability.
95. What is Downtime?
System not available.
96. What is Release?
Deploying software.
97. What is Rollback?
Returning to old version.
98. What is Artifact repository?
Stores build files.
99. What is Orchestration?
Managing multiple systems.
100. Why DevOps?
To deliver software faster, safer and efficiently.
Source: sureshtechlabs.com