300-910 Sample Questions & Answers

A Kubernetes Service provides a stable network abstraction layer for a set of pods. It creates a single, stable IP address and DNS name (e.g., my-service.default.svc.cluster.local) that other applications within the cluster can use to access the pods managed by the Deployment. The Service automatically handles load balancing across the pods, even as they are created or destroyed. An Ingress is for external access, a Pod is the workload itself, and a ConfigMap is for configuration data.

The primary goal of chaos engineering is to build confidence in the system's ability to withstand turbulent conditions in production. By injecting latency, the team is proactively testing whether the application's built-in resilience patterns (like timeouts, retries, and circuit breakers) behave as expected. This helps uncover hidden weaknesses before they cause a real-world outage.

Static Application Security Testing (SAST) analyzes an application's source code, bytecode, or binary code for security vulnerabilities without executing the program. Because it works directly on the code, it can be integrated very early in the SDLC, such as upon a code commit or pull request, to find issues like SQL injection or buffer overflows before the application is even built. DAST requires a running application, IAST combines both, and penetration testing is typically a later-stage manual or automated process.

Jenkins is renowned for its massive plugin ecosystem, which allows for extensive customization and integration with virtually any tool. It is an open-source, self-hosted solution, which satisfies the security compliance requirement. Its long history has resulted in a very large and active community, providing ample support and resources. While Drone is also self-hosted, its plugin ecosystem is smaller. Travis CI is primarily a cloud-based SaaS offering.

This is a classic transitive dependency conflict. The requests library itself depends on urllib3. If version 2.25.1 of requests requires a version of urllib3 that is outside the =1.25.4 range, pip will be unable to find a compatible set of packages, leading to a resolution error. This highlights the complexity of managing dependencies in modern applications.

In Ansible, the state: present parameter is used to ensure that a resource (like a VLAN, user, or package) exists. If the VLAN is not configured, Ansible will create it. If the VLAN already exists as defined, Ansible will report 'ok' and make no changes. This is the core of idempotency. The opposite is state: absent, which ensures the resource does not exist.

A service mesh is a dedicated infrastructure layer for managing service-to-service communication. It provides features like mutual TLS (mTLS) for security, advanced traffic management (e.g., circuit breaking, retries) for performance and resilience, and detailed telemetry (metrics, logs, traces) for observability. While an API Gateway handles north-south (ingress) traffic, a service mesh is specifically designed to manage east-west traffic between microservices, making it the ideal choice for this scenario.

The main advantage of using managed services ('buy') is the reduction of operational burden. The cloud provider handles complex and time-consuming tasks like OS patching, database software updates, automated backups, and configuring high availability/failover. This allows a small team to focus on developing the application's core features and accelerate time-to-market, which is critical given the tight deadline.

Slow and flaky tests can severely hinder developer productivity by blocking the main CI/CD pipeline. The best practice is to move them to a separate, parallel pipeline (often called an acceptance or end-to-end test pipeline). This allows the primary pipeline (with fast, reliable unit and integration tests) to complete quickly, providing rapid feedback. The slower tests still provide value by running against a stable build, but they don't become a bottleneck for every commit.

This statement is false. A threat model is a living document that should be reviewed and updated throughout the entire software development lifecycle. New features, changes in architecture, newly discovered vulnerabilities, or evolving threat landscapes all necessitate revisiting and updating the threat model to ensure it accurately reflects the current security posture of the application.