36 practice questions with answers for DevOps interviews in Thiruvananthapuram.
DevOps jobs in Thiruvananthapuram
Thiruvananthapuram's Technopark is one of India's oldest IT parks, hosting IT-services, product and engineering-services companies. Data and testing teams here often work with global clients in finance, travel and healthcare.
Below are 36 questions that match the mix of service, product and domain employers hiring junior devops engineers in Thiruvananthapuram.
Solved for ThiruvananthapuramStart practicing
3 QUESTIONS FREESign up to unlock the full question bank and track your progress.Unlock every question and answer, then continue practising company-wise and package-wise.
A VPC is your private network with a CIDR range like 10.0.0.0/16. It is split into subnets in each Availability Zone. Public subnets have a route to an Internet Gateway; private subnets reach the internet only through a NAT Gateway in a public subnet. Route tables control traffic, security groups and NACLs filter it, and VPC endpoints give private access to services like S3.
02
Pods are running but the service is not reachable. How do you debug it?
Run kubectl get endpoints <svc>; if empty, the service selector does not match the pod labels or pods are not ready. Check that the service targetPort matches the container port. Test from a debug pod with curl svc-name.namespace:port to separate DNS from app issues. Then check network policies blocking traffic and, for external access, the ingress rules and load balancer health checks.
git cherry-pick <hash> applies the changes of one specific commit onto your current branch as a new commit. It is useful to bring a hotfix from main into a release branch without merging everything else. Overusing it creates duplicate commits with different hashes and can cause confusing conflicts later, so prefer merging when you need a whole set of changes.
04
How do you keep yourself updated with new DevOps tools and practices?
I follow official release notes for tools I use, such as Kubernetes and Terraform, and read a few engineering blogs and CNCF updates weekly. I learn by doing, so I try new tools in a small home lab or free cloud tier before suggesting them. I also prepare for certifications to structure my learning, and share short notes with my team.
05
How do you build and push a Docker image from a pipeline?
# shell steps in any CI tool
IMAGE=registry.example.com/shop/api
TAG=$(git rev-parse --short HEAD)
echo "$REG_PASS" | docker login registry.example.com -u "$REG_USER" --password-stdin
docker build -t $IMAGE:$TAG .
docker push $IMAGE:$TAG
Tag with the commit SHA so each image is traceable and immutable; avoid relying on latest. Credentials come from the CI secret store, and --password-stdin keeps them out of process lists.
06
What is a webhook and how does it trigger a build?
A webhook is an HTTP callback: when an event happens in the Git server, such as a push or pull request, it sends a POST request with event details to a configured URL. Jenkins or another CI tool receives it and starts the matching pipeline immediately. This is better than polling the repository every few minutes, which wastes resources and delays feedback.
The kubelet cannot pull the image. Check the image name and tag for typos and confirm the tag exists in the registry. For private registries, verify an imagePullSecret is set and has valid credentials, or that node IAM roles allow pulling from ECR. Also check network access from nodes to the registry and registry rate limits. kubectl describe pod shows the exact error.
08
The application cannot connect to an RDS database. What do you check?
Confirm the endpoint, port, username and password. Check that the RDS security group allows inbound traffic on the database port from the application's security group, and that both are in reachable subnets of the same VPC or peered networks. Test with nc -zv endpoint 5432 from the app host. Also check the instance status, max connections and SSL requirements.
09
A pod is stuck in Pending state. What could be the reasons?
Pending means it has not been scheduled or its volumes are not ready. kubectl describe pod shows the scheduler's reason. Common causes are insufficient CPU or memory on nodes for the requests, node selectors, affinity or taints that no node satisfies, a PersistentVolumeClaim that cannot bind, or a resource quota being exceeded. Fix the spec or add nodes with the cluster autoscaler.
A common pipeline is checkout, build or compile, unit tests, static analysis and security scans, packaging into an artefact or container image, pushing to a registry, deploying to a test or staging environment, running integration or smoke tests, an approval gate, and production deployment with monitoring. Fast checks run first so developers get feedback within minutes and slow tests run later.
11
Tell me about a time you introduced a new tool or practice to your team.
Situation: new developers took two days to set up our app locally because of different OS versions and manual database installs. Task: I wanted to make onboarding easy. Action: I created a Docker Compose setup with the app, database and seed data, wrote a short README and demoed it. Result: setup dropped to under an hour and the team adopted it for CI.
The firmware (BIOS or UEFI) runs hardware checks and loads the bootloader, usually GRUB. GRUB loads the kernel and the initramfs, which contains drivers needed to mount the real root file system. The kernel then starts PID 1, which is systemd on most modern distributions. systemd mounts file systems and starts services in parallel according to unit dependencies and the default target.
13
You deleted a local branch that had unmerged commits. How do you recover it?
Git keeps unreferenced commits for a while. Run git reflog to see recent HEAD positions and find the last commit of that branch, or check the hash printed when you deleted it. Then recreate the branch with git branch feature-x <hash>. Reflog is local only, so this works on the same machine, and entries expire after about 90 days by default.
14
Write a production-ready Dockerfile for a Node.js application.
FROM node:20-alpine
WORKDIR /app
ENV NODE_ENV=production
COPY package.json package-lock.json ./
RUN npm ci --omit=dev
COPY . .
USER node
EXPOSE 3000
CMD ["node", "server.js"]
Dependencies are copied and installed before source code so the layer is cached. npm ci gives reproducible installs, USER node avoids running as root, and exec form CMD lets the app receive signals.
15
Write a multi-stage Dockerfile for a Java Spring Boot application.
FROM maven:3.9-eclipse-temurin-21 AS build
WORKDIR /src
COPY pom.xml .
RUN mvn -B dependency:go-offline
COPY src ./src
RUN mvn -B package -DskipTests
FROM eclipse-temurin:21-jre-alpine
WORKDIR /app
COPY --from=build /src/target/*.jar app.jar
RUN adduser -D appuser
USER appuser
EXPOSE 8080
ENTRYPOINT ["java", "-jar", "app.jar"]
The final image has only the JRE and the JAR, not Maven or source.
16
How do Docker image layers and build caching work?
Each Dockerfile instruction like RUN, COPY or ADD creates a layer. Docker caches layers and reuses them if the instruction and its inputs have not changed; once one layer changes, all later layers rebuild. So copy dependency files and install dependencies first, then copy source code. That way code changes do not reinstall all packages, and builds become much faster.
17
Explain the Kubernetes Service types ClusterIP, NodePort and LoadBalancer.
A Service gives pods a stable IP and DNS name and load balances across them using label selectors. ClusterIP, the default, is reachable only inside the cluster. NodePort also opens a port, 30000 to 32767, on every node. LoadBalancer additionally asks the cloud provider to create an external load balancer pointing to the service. Each type builds on the previous one.
18
You pushed a broken commit to the shared main branch and the build is failing. What do you do?
First restore a green main quickly: run git revert <hash> and push, which adds an undo commit without rewriting history that others have pulled. Tell the team in the channel. Then fix the issue on a branch with a proper pull request and tests. Avoid git reset with force push on main; branch protection rules should block it anyway.
19
Your service has used its entire error budget halfway through the quarter. What happens next?
Following the agreed error budget policy, the team pauses risky feature launches and focuses on reliability work: fixing the top causes of failures from post-mortems, adding tests, improving rollbacks and canaries. Product and engineering leads review the plan together. Once the budget recovers in the rolling window, normal releases resume. If the SLO is unrealistic, revisit it with data.
A zombie is a process that has exited but whose parent has not yet read its exit status with wait(), so it still holds a PID entry and shows state Z. An orphan is a running process whose parent died; it is adopted by PID 1, which reaps it later. Many zombies indicate a buggy parent; fixing or restarting the parent clears them.
21
Your Docker image is 1.5 GB. How do you reduce its size?
Switch to a slimmer base image such as a slim or distroless variant. Use a multi-stage build so compilers and build caches stay out of the final image. Combine package installs and clean caches in the same RUN layer. Add a .dockerignore to exclude .git, node_modules and test data. Then inspect remaining layers with docker history or the dive tool.
22
How do you create an EKS cluster with eksctl and connect kubectl to it?
Collect alert data for a few weeks: which fired, how often, and whether anyone acted. Delete or downgrade non-actionable alerts, tune thresholds and add for durations, and group duplicates in Alertmanager. Fix the recurring root causes behind the top alerts and automate common fixes. Move to SLO-based alerts and make sure rotations are fair with follow-up time after bad nights.
25
You need to bring existing manually created cloud resources under Terraform. How?
Write the resource blocks in code, then import the real resources into state. Since Terraform 1.5 you can declare import blocks with the resource ID and run plan; terraform plan -generate-config-out can even draft the configuration. Older versions use the terraform import CLI command. Run plan until it shows no changes, which proves code matches reality.
26
Write a Deployment manifest with 3 replicas, resource limits and a readiness probe.
Handlers are tasks that run only when notified by another task that reported a change, and they run once at the end of the play even if notified many times.
tasks:
- name: Update app config
ansible.builtin.copy:
src: app.conf
dest: /etc/app/app.conf
notify: Restart app
handlers:
- name: Restart app
ansible.builtin.service:
name: app
state: restarted
This avoids restarting services when nothing changed.
All three move the current branch pointer to another commit. --soft keeps your changes staged, useful for recombining commits. --mixed, the default, keeps changes in the working directory but unstaged. --hard discards changes in both staging and working directory, so uncommitted work is lost. Lost commits can usually still be found with git reflog for a while.
29
Builds fail randomly because of flaky tests. How do you handle it?
First identify flaky tests by tracking which tests fail and pass on the same commit. Quarantine them into a separate non-blocking job so the main pipeline stays trustworthy, and raise tickets with owners. Common causes are timing assumptions, shared test data, order dependence and external services. Blind automatic retries hide real bugs, so use them only briefly while fixing the root cause.
30
How do you perform a rolling update and roll back a Deployment?
# update the image
kubectl set image deployment/api api=registry.example.com/api:1.5.0
kubectl rollout status deployment/api
# history and rollback
kubectl rollout history deployment/api
kubectl rollout undo deployment/api
kubectl rollout undo deployment/api --to-revision=3
# pause or restart
kubectl rollout pause deployment/api
kubectl rollout restart deployment/api
In GitOps setups, you change the image tag in Git instead and let Argo CD apply it.
31
Two engineers ran terraform apply at the same time. What could go wrong and how do you prevent it?
Without locking, both runs read the same state and write conflicting updates, which can corrupt state or create duplicate resources. Use a remote backend with state locking so the second run waits or fails. Better still, run apply only from a CI pipeline on merge to main, so changes are serialised and reviewed. If a lock is stuck after a crash, use terraform force-unlock carefully.
32
What is a multi-stage Docker build and why use it?
A multi-stage build uses several FROM instructions in one Dockerfile. Early stages contain compilers and build tools to produce the artefact; the final stage starts from a small runtime image and copies only the built output with COPY --from. The result is a much smaller image with fewer vulnerabilities, because build tools, source code and caches never reach production.
33
An Ansible playbook run against 100 servers failed on 7 of them. What do you do?
Check the output and the retry file or failed host list to see the error on those hosts, for example unreachable SSH, a missing package repo or full disk. Fix the cause, then rerun only those hosts with --limit. Because tasks are idempotent, rerunning on successful hosts is also safe. For rolling changes, use serial and max_fail_percentage to stop early on failures.
Idempotency means running the same playbook many times gives the same result without unwanted changes. Modules check current state first: the apt module installs a package only if missing and reports ok instead of changed. The shell and command modules are not idempotent by default, so use creates, removes or changed_when conditions, or prefer a dedicated module.
35
You need one pipeline that deploys to dev, staging and production with approval before production. How do you design it?
Build and test once, publish a versioned artefact, then promote it through environments. Dev deploys automatically on merge, staging deploys after dev smoke tests, and production waits for a manual approval from authorised people using a Jenkins input step or GitHub environment protection rules. Keep environment-specific settings in config files or parameters, not separate pipelines, and record who approved each release.
36
How do you count unique client IP addresses in an nginx access log?
awk '{print $1}' /var/log/nginx/access.log | sort | uniq -c | sort -rn | head -10
# total number of unique IPs
awk '{print $1}' access.log | sort -u | wc -l
The first field in the default log format is the client IP. uniq -c only collapses adjacent lines, so sort must run before it; the final sort -rn shows the busiest IPs first.
Few big employers listed in Thiruvananthapuram?
Many Thiruvananthapuram candidates also apply to teams in Bangalore and to remote or hybrid roles. Practise the Bangalore set as well.
Which companies hire DevOps professionals in Thiruvananthapuram?
Companies with large offices in Thiruvananthapuram include many IT services and product firms. Use their company pages below to practise employer-specific sets.
Are DevOps interviews in Thiruvananthapuram different from other cities?
The questions depend more on the company than the city. Thiruvananthapuram's mix of employers decides the style: Data and testing teams here often work with global clients in finance, travel and healthcare
How do I find DevOps jobs in Thiruvananthapuram?
Shortlist companies with Thiruvananthapuram offices, keep your CV focused on DevOps projects, apply on company career pages and job portals with the Thiruvananthapuram filter, and practise the questions on this page before each interview.