Guides

How to Prepare for a DevOps Interview in 30 Days

By Ravindra Bagale, DevOps trainer · LinkedIn · Published: 28 October 2026 · Last updated: 28 October 2026

Thirty days can prepare you for a DevOps interview if every day has a lab exit. This plan covers Linux, Docker, one pipeline, one Terraform apply and mocks — the path Infosys, TCS, Amazon and Flipkart-style rounds expect.

Language: English · मराठी · हिंदी

Why a 30-day plan works

Panic studying five tools the night before an Infosys or Amazon round fails. A calendar with exit checks works.

Why: Time boxing beats random YouTube. What: Four weeks with labs and mocks. How: Follow the day blocks. Tick exits in writing.

Concept 1: Days 1-7 Linux and Git

Why: Most first rounds at Infosys and TCS start with Linux and Git. What: systemctl, logs, disk, SSH keys, git log and branches. How: One exit check per day. Write answers in a notebook.

Example 1: Day plan file

Type this:

printf '%s\n' 'd1: systemctl' 'd2: journalctl' 'd3: df/du' 'd4: ss/curl' 'd5: git log' 'd6: branch/PR' 'd7: mock linux' > /tmp/w1.txt
wc -l < /tmp/w1.txt

You will see:

7

What it means: Seven days, seven exits.

Example 2: Linux exit sample

Type this:

systemctl is-system-running 2>/dev/null || echo running-ok

You will see:

running-ok

What it means: You can talk about service state.

Example 3: Git init exit

Type this:

cd /tmp && rm -rf iview && mkdir iview && cd iview && git init -q -b main && printf 'a\n' > a.txt && git add a.txt && git -c user.email=a@b.c -c user.name=A commit -q -m init && git log --oneline | wc -l

You will see:

1

What it means: You must read a log aloud in interview.

Concept 2: Days 8-14 Docker

Why: Docker questions separate theory-only freshers. What: Image, container, Dockerfile, Compose, logs and exec. How: Ship one small app you can explain end to end.

Example 4: Docker version

Type this:

docker version --format '{{.Server.Version}}' 2>/dev/null || echo install-docker-first

You will see:

install-docker-first

What it means: Engine must run before day 8 labs (install if needed).

Example 5: Explain ports

Type this:

printf '%s\n' 'host:8080 -> container:80'

You will see:

host:8080 -> container:80

What it means: Interviewers ask what -p means.

Example 6: Compose mind-set

Type this:

printf '%s\n' 'services: web, db' 'one network' 'one volume for db'

You will see:

services: web, db
one network
one volume for db

What it means: Say this aloud in mocks.

Concept 3: Days 15-21 CI and Terraform

Why: Hiring managers want one green pipeline and one infra change story. What: Actions or Jenkins + terraform plan/apply on a tiny resource. How: Record screenshots of green runs (no secrets).

Example 7: CI checklist

Type this:

printf '%s\n' 'checkout' 'test' 'build' 'push-or-artifact'

You will see:

checkout
test
build
push-or-artifact

What it means: Name stages without notes.

Example 8: Terraform version

Type this:

terraform version 2>/dev/null | head -1 || echo install-terraform

You will see:

install-terraform

What it means: Install v1.x for labs; pin in real teams.

Example 9: Plan story

Type this:

printf '%s\n' 'I ran terraform plan, saw 1 to add, applied, then destroyed the lab.'

You will see:

I ran terraform plan, saw 1 to add, applied, then destroyed the lab.

What it means: Destroy labs to avoid bills.

Concept 4: Days 22-30 mocks and company packs

Why: Silence in a mock becomes silence in the real round. What: Timed answers, incident stories, company-flavored questions. How: Two mocks with a friend. Use Interview Hub topics.

Example 10: Timer drill

Type this:

python3 -c "print('answer_in_90_seconds')"

You will see:

answer_in_90_seconds

What it means: Keep answers under 90 seconds unless asked to deep dive.

Example 11: Company packs

Type this:

printf '%s\n' 'Infosys: Linux+Jenkins' 'Amazon: ownership+metrics' 'Flipkart: scale+K8s basics'

You will see:

Infosys: Linux+Jenkins
Amazon: ownership+metrics
Flipkart: scale+K8s basics

What it means: Match prep to JD.

Example 12: Gap log

Type this:

printf '%s\n' 'weak: networking' 'drill: ss -tulpn tomorrow'

You will see:

weak: networking
drill: ss -tulpn tomorrow

What it means: Close one gap per day.

Week checklist

Suppose: TCS-style screening

Expect Linux commands and basic Docker. Do not skip week 1.

Suppose: Product company

Expect ownership stories and metrics from your labs.

Check yourself (quiz)

30 days = calendar + exits + mocks. Linux first. One pipeline story. Speak aloud. Did you understand? Let us try it once more.