30+ Platform Engineer Interview Questions and Answers

Check if a given singly linked list is a palindrome or not.

• Use two pointers approach to find the middle of the linked list

• Reverse the second half of the linked list

• Compare the first half with the reversed second half to determine if it's a palindrome

SQL statement to retrieve all records from a database table named 'users'.

• Use SELECT * FROM users;

• Replace '*' with specific column names if needed.

• Add WHERE clause for filtering data.

Designing a coffee vending machine system.

• Identify the types of coffee to be offered

• Determine the payment methods (cash, card, mobile payment)

• Select the appropriate hardware components (dispenser, grinder, etc.)

• Develop software for user interface and payment processing

• Implement sensors for inventory management

• Ensure regular maintenance and cleaning

• Consider energy efficiency and sustainability

IBGP setup can lead to unintended transit AS issues; implement route filtering to prevent this.

• IBGP routers do not advertise routes learned from one IBGP peer to another, preventing loops.

• Without proper configuration, internal routers may inadvertently become transit AS for external traffic.

• Use route filtering or prefix lists to control which routes are advertised to prevent transit behavior.

• Implementing a route reflector or confederation can help manage IBGP sessions without...read more

Exploratory Data Analysis (EDA) of a dataset using Python's df.describe function.

• Use df.describe() to get summary statistics of the dataset.

• Check for missing values, outliers, and distribution of data.

• Visualize the data using plots like histograms, box plots, and scatter plots.

• Use additional libraries like matplotlib and seaborn for more advanced visualizations.

Compare software version strings by splitting, converting to integers, and comparing each segment for equality.

• Split the version strings by '.' to get individual components.

• Convert each component to an integer for accurate comparison.

• Compare the components one by one until a difference is found.

• Example: '1.2.3' vs '1.2.10' - compare 1, 2, and then 3 vs 10.

• If all components are equal, the versions are the same.

BGP operates at the Application layer (Layer 7) of the OSI model, facilitating inter-domain routing between autonomous systems.

• BGP (Border Gateway Protocol) is used for routing between different autonomous systems on the internet.

• It operates at the Application layer, which is responsible for end-user services and application-level protocols.

• BGP uses TCP (Transmission Control Protocol) for reliable communication, which operates at the Transport layer (Layer 4).

• Example: BGP is ...read more

I have used AWS core services such as EC2, S3, RDS, and Lambda for infrastructure provisioning, storage, database management, and serverless computing.

• EC2 - for provisioning virtual servers to run applications

• S3 - for scalable object storage

• RDS - for managed relational databases

• Lambda - for serverless computing and running code without provisioning or managing servers

Scaling patterns for distributed system

• Horizontal scaling - adding more instances of the same component

• Vertical scaling - increasing the resources of a single instance

• Sharding - partitioning data across multiple nodes

• Caching - storing frequently accessed data in memory

• Load balancing - distributing traffic across multiple nodes

• Auto-scaling - automatically adjusting resources based on demand

Helm is a package manager for Kubernetes that helps in deploying applications.

• Create a Helm chart for the application

• Customize values in the values.yaml file

• Run 'helm install ' to deploy the application

• Use 'helm upgrade' to make changes to the deployment

• Monitor the deployment using 'helm status'

The candidate is asked to share and explain code on the screen.

• Prepare to explain the code structure, logic, and any specific functions or methods used.

• Highlight any key features or optimizations in the code.

• Be ready to answer questions about the code's functionality and potential improvements.

Rearranging a string to form the maximum possible number involves sorting its digits in descending order.

• Sort Digits: Convert the string into an array of characters, sort them in descending order, and then join them back into a string.

• Example: For the input '321', sorting gives '321'.

• Handling Zeros: If the string contains zeros, ensure they are placed at the end after sorting.

• Example: For '3201', the result after sorting is '3210'.

• Edge Cases: Consider single-digit strings or ...read more

Effective observability in cloud involves monitoring, logging, and tracing to ensure system health and performance.

• Implement centralized logging using tools like ELK Stack (Elasticsearch, Logstash, Kibana) for better log management.

• Use monitoring solutions like Prometheus or Grafana to visualize metrics and set up alerts for anomalies.

• Incorporate distributed tracing with tools like Jaeger or Zipkin to track requests across microservices.

• Leverage cloud-native observability too...read more

Kubernetes is a container orchestration platform that automates the deployment, scaling, and management of containerized applications.

• Kubernetes follows a master-slave architecture where the master node controls the cluster and the worker nodes run the containers.

• Key components of Kubernetes architecture include Pods, Nodes, Clusters, Services, and Controllers.

• Kubernetes administration involves tasks like deploying applications, scaling resources, monitoring cluster health, a...read more

Kubernetes is a container orchestration platform that automates deployment, scaling, and management of containerized applications.

• Kubernetes has several core components including the API server, etcd, kubelet, kube-proxy, and the container runtime.

• The API server is the central management point for Kubernetes and exposes the Kubernetes API.

• etcd is a distributed key-value store that stores the configuration data for Kubernetes.

• kubelet is responsible for managing the state of ea...read more

useEffect is a hook in React that allows performing side effects in function components.

• Used to perform side effects in function components

• Runs after every render by default

• Can specify dependencies to control when it runs

VXLAN enhances network scalability, flexibility, and isolation in virtualized environments through encapsulation and overlay networks.

• Scalability: Supports up to 16 million unique segments, far exceeding VLAN limits.

• Overlay Networking: Allows for the creation of virtual networks over existing physical infrastructure.

• Multitenancy: Provides isolation between different tenants in a cloud environment, enhancing security.

• Mobility: Enables seamless VM migration across data centers ...read more

Tcpdump is a command-line packet analyzer used to capture and analyze network traffic.

• Tcpdump captures packets on a network interface, allowing for real-time analysis.

• Basic command: 'tcpdump -i eth0' captures packets on the eth0 interface.

• Use filters to capture specific traffic, e.g., 'tcpdump -i eth0 port 80' for HTTP traffic.

• Output can be saved to a file with '-w', e.g., 'tcpdump -i eth0 -w capture.pcap'.

• Analyze saved files with 'tcpdump -r capture.pcap' or use Wireshark fo...read more

Find the next lexicographical permutation of a sequence of numbers.

• Identify the longest non-increasing suffix.

• Find the pivot just before the suffix.

• Swap the pivot with the smallest element in the suffix that is larger than the pivot.

• Reverse the suffix to get the next permutation.

Implement search in binary tree using recursion

• Start at the root node

• Compare the target value with the current node value

• If target is less than current node value, search left subtree; if greater, search right subtree

• Repeat process until target is found or node is null

A prime number is a number greater than 1 that has no positive divisors other than 1 and itself.

• Check if the number is greater than 1

• Iterate from 2 to the square root of the number and check if it is divisible by any number

• If it is not divisible by any number, then it is a prime number

Apache Kafka is a popular platform for ingesting streaming data.

• Apache Kafka is a distributed streaming platform that can handle high volumes of data in real-time.

• It allows for the ingestion, storage, and processing of streaming data from various sources.

• Kafka provides fault tolerance, scalability, and high throughput for streaming data pipelines.

CI-CD pipeline automates software delivery process, from code changes to production deployment.

• Automates building, testing, and deploying code changes

• Ensures code quality and consistency

• Facilitates faster and more frequent releases

• Integrates with version control systems like Git

• Tools like Jenkins, GitLab CI/CD, and CircleCI are commonly used

Optimizing database involves indexing, query optimization, normalization, and proper hardware configuration.

• Use indexing to speed up data retrieval

• Optimize queries by avoiding unnecessary joins and using appropriate indexes

• Normalize database tables to reduce redundancy and improve data integrity

• Consider hardware configuration like storage type and memory allocation for optimal performance

Netflix OSS is a set of open-source software tools and libraries developed by Netflix for building and managing microservices architecture.

• Netflix OSS includes tools like Eureka for service discovery, Ribbon for client-side load balancing, and Hystrix for fault tolerance.

• It allows developers to build resilient, scalable, and fault-tolerant distributed systems.

• Netflix OSS promotes the use of microservices architecture by providing tools to simplify the development and manageme...read more

Switching is important in networking to enable communication between devices on different networks.

• Switching allows devices on the same network to communicate with each other by forwarding data packets based on MAC addresses.

• Switches operate at Layer 2 of the OSI model and use MAC addresses to make forwarding decisions.

• Switching reduces network congestion by only sending data to the intended recipient instead of broadcasting to all devices on the network.

Cosine similarity is a measure of similarity between two non-zero vectors of an inner product space.

• It measures the cosine of the angle between two vectors.

• Values range from -1 (completely opposite) to 1 (completely similar).

• Used in information retrieval, text mining, and recommendation systems.