Linux Operating Systems and Core Utilities
Your mastery of Linux forms the bedrock of the DevOps role at Captivation Software. Interviewers evaluate your ability to diagnose performance bottlenecks, manage system services, and write clean, maintainable automation scripts. Strong performance means instantly identifying whether a performance issue stems from I/O wait, memory exhaustion, or network saturation without guessing.
Be ready to go over:
- Kernel parameters and resource tuning – Understanding how to adjust file descriptors, swappiness, and network buffers for high-throughput applications.
- Process management and diagnostics – Using tools like
strace, top, netstat, and journalctl to trace system calls and isolate failing services.
- Advanced shell scripting – Writing robust Bash or Python scripts complete with error trapping, logging, and idempotency.
- Advanced concepts (less common) – Linux namespaces, cgroups implementation, custom systemd service file creation, and immutable infrastructure patterns.
Example questions or scenarios:
- "A core service is crashing intermittently with out-of-memory errors on a production node. Walk us through your exact debugging process."
- "How would you write a script to monitor disk usage across a fleet of servers and automatically archive old logs when thresholds are exceeded?"
Continuous Integration and Continuous Deployment (CI/CD)
Automation velocity and deployment safety are critical evaluation vectors. Interviewers assess how you design pipelines that accelerate delivery while catching defects early. Strong candidates demonstrate a deep understanding of pipeline triggers, artifact management, automated testing integration, and zero-downtime deployment strategies.
Be ready to go over:
- Pipeline architecture – Structuring multi-stage pipelines in tools like GitLab CI or Jenkins with parallel execution and conditional branching.
- Artifact versioning and security – Managing container registries, dependency caching, and vulnerability scanning during builds.
- Deployment strategies – Implementing blue-green deployments, canary releases, and rolling updates to eliminate user-facing downtime.
- Advanced concepts (less common) – GitOps workflows using tools like ArgoCD, custom runner autoscaling, and immutable artifact promotion across air-gapped environments.
Example questions or scenarios:
- "Describe how you would implement a secure CI/CD pipeline for a microservices architecture that requires automated security scanning before staging deployment."
- "How do you handle database schema migrations within a continuous deployment pipeline without breaking running application instances?"
Infrastructure as Code and Cloud Orchestration
Provisioning and managing infrastructure programmatically is an everyday expectation. Interviewers look for your ability to write modular, reusable infrastructure code and manage cloud resources securely. Strong performance requires demonstrating a firm grasp of state management, dependency graphing, and drift detection.
Be ready to go over:
- Terraform state management – Handling remote state locking, workspace segregation, and refactoring existing infrastructure without destruction.
- Cloud networking and security – Architecting Virtual Private Clouds (VPCs), subnets, security groups, and IAM policies in AWS.
- Configuration management – Using Ansible playbooks to configure instances idempotently after initial provisioning.
- Advanced concepts (less common) – Custom Terraform provider development, dynamic policy-as-code enforcement using Sentinel or OPA, and multi-region failover strategies.
Example questions or scenarios:
- "How do you structure a large Terraform repository shared by multiple engineering teams to prevent conflicting state updates?"
- "Walk us through how you configure a secure network boundary between public-facing load balancers and internal data stores."
Containers and Orchestration
Containerization is central to modern deployments at the company. You will be evaluated on your ability to containerize legacy and modern applications, manage orchestration clusters, and ensure high availability. Strong candidates show fluency in container networking, storage drivers, and cluster health monitoring.
Be ready to go over:
- Docker best practices – Minimizing attack surfaces, utilizing multi-stage builds, and managing non-root container execution.
- Kubernetes cluster operations – Deploying workloads using Pods, Deployments, Services, Ingress controllers, and ConfigMaps.
- Observability and logging – Aggregating metrics and logs using tools such as Splunk, Grafana, Prometheus, and Kafka.
- Advanced concepts (less common) – Custom Kubernetes operators, Service Mesh implementation (like Istio), and persistent volume encryption.
Example questions or scenarios:
- "Explain how a packet travels from an external user to a specific container inside a Kubernetes cluster utilizing an Ingress controller."
- "How do you monitor and debug networking latency between microservices running across different worker nodes?"