As a DevOps Engineer at Ericsson, you are stepping into a role that sits at the critical intersection of telecommunications infrastructure and modern software engineering. Ericsson is a global leader in 5G, networking, and telecommunications, meaning the systems you build, deploy, and maintain operate at an extraordinary scale. Your work directly impacts how millions of users connect, communicate, and consume data worldwide.

In this position, you are not just maintaining pipelines; you are driving the automation and reliability of massive, distributed networks. You will collaborate with software developers, network architects, and product teams to ensure that highly complex, mission-critical applications are deployed seamlessly. The complexity of Ericsson’s environment requires a deep understanding of containerization, system protocols, and advanced programming to manage infrastructure that cannot afford downtime.

This role is incredibly strategic. You will be tasked with modernizing legacy systems, introducing robust CI/CD practices, and ensuring that Ericsson remains agile in a highly competitive telecom landscape. Expect to tackle unique challenges involving edge computing, cloud-native 5G core networks, and high-throughput data processing. If you are passionate about building resilient systems at a global scale, this role offers an unparalleled opportunity to shape the future of connectivity.

The following questions are representative of what candidates face during the DevOps Engineer interview process at Ericsson. They are designed to illustrate the pattern and rigor of the evaluation, helping you focus your preparation on the right concepts.

Coding and Algorithms

These questions test your software engineering fundamentals, focusing heavily on data structures and advanced programming concepts.

• Write a Python program to find the longest substring without repeating characters in a given string.
• Implement a thread-safe rate limiter in Python to control API request traffic.

Preparing for the DevOps Engineer interviews at Ericsson requires a balanced approach. You must demonstrate not only deep operational knowledge but also strong software engineering fundamentals. The hiring team will evaluate you across several core dimensions to ensure you can handle the rigorous technical demands of the role.

Role-related knowledge – This covers your core domain expertise in modern infrastructure. Interviewers will test your proficiency with container orchestration (like Kubernetes), CI/CD pipelines, cloud platforms, and system protocols. You can demonstrate strength here by clearly explaining your past architectural decisions and how you handle system scalability.

Coding and Problem-solving ability – Unlike some organizations where DevOps is purely operational, Ericsson places a heavy emphasis on programming and algorithmic thinking. You will be evaluated on your ability to write clean, efficient code (often in Python) and your understanding of data structures. You can excel by practicing complex coding challenges and explaining your logical approach out loud.

System Architecture & Infrastructure – This evaluates your ability to design, scale, and secure large distributed systems. Interviewers want to see how you approach high availability, disaster recovery, and network configuration. You will stand out by showing a holistic understanding of how software interacts with underlying network layers.

Culture fit / values – Ericsson values collaboration, continuous learning, and adaptability. You will be assessed on how you communicate complex technical concepts, how you navigate ambiguity, and how you collaborate with cross-functional teams. Showcasing a proactive attitude and a history of driving technical improvements will strongly align with their values.

The interview process for a DevOps Engineer at Ericsson is rigorous, multi-staged, and highly technical. While the exact flow can vary slightly by location and team, you should expect a comprehensive evaluation that tests both your theoretical knowledge and your hands-on coding abilities. The process typically begins with a standard recruiter screen to align on expectations, location preferences (such as hybrid or on-site requirements), and compensation.

Following the initial screen, Ericsson frequently utilizes asynchronous written assessments. Candidates often report receiving a technical "package" that can include a timed coding challenge in a language of your choice, as well as multiple-choice tests covering DevOps concepts, Kubernetes, and network protocols. In some regions, this stage may also include extensive personality and cognitive (IQ) assessments to evaluate your problem-solving baseline and cultural alignment.

The final stages consist of deep-dive technical interviews with hiring managers and senior engineers. These rounds are intensive and often feature complex programming tests, architectural discussions, and behavioral evaluations. Ericsson’s philosophy is deeply rooted in data and proven technical capability, so expect interviewers to probe deeply into your past experiences and ask you to solve hard, algorithmic problems on the spot.

This visual timeline outlines the typical progression of the Ericsson interview process, from the initial HR screen through the written assessments and final technical rounds. Use this to pace your preparation, ensuring you are ready for the early written technical tests before shifting focus to live coding and architectural deep dives. Keep in mind that the exact order of the technical and behavioral rounds may fluctuate depending on the specific hiring manager.

To succeed in the DevOps Engineer interviews at Ericsson, you must be prepared for a wide-ranging technical evaluation. The process is designed to ensure you possess both the operational expertise to manage infrastructure and the software engineering skills to automate it.

Coding and Data Structures

At Ericsson, a DevOps Engineer is expected to be a highly capable programmer. You will face complex coding interviews that go beyond simple scripting. Interviewers will evaluate your grasp of data structures, algorithms, and advanced programming concepts, frequently focusing on Python. Strong performance means writing optimized, bug-free code while clearly communicating your time and space complexity trade-offs.

Be ready to go over:

• Advanced Python – Deep understanding of Python internals, decorators, generators, and object-oriented programming.
• Data Structures – Practical application of arrays, hash maps, trees, and graphs to solve operational problems.
• Algorithmic Problem Solving – Approaching complex logical puzzles and optimizing brute-force solutions.
• Advanced concepts (less common) – Multi-threading, concurrency, and memory management in your language of choice.

Example questions or scenarios:

• "Write a Python script to parse a massive log file, identify specific error patterns using regex, and output the frequency of each error in descending order."
• "Implement a data structure that can efficiently manage and retrieve the state of thousands of concurrent network connections."
• "Solve this complex algorithmic challenge [often similar to medium/hard LeetCode problems] using a language of your choice."

DevOps Principles and Infrastructure

This area tests your foundational knowledge of modern infrastructure management. Ericsson heavily relies on containerization and automated pipelines to deliver software. Interviewers will look for a deep, practical understanding of how to build, deploy, and maintain resilient systems. Strong candidates will not only know the tools but understand the underlying mechanics of how they operate.

Be ready to go over:

• Kubernetes Architecture – Deep dive into pods, nodes, control planes, ingress controllers, and stateful deployments.
• CI/CD Pipelines – Designing secure, automated release pipelines using tools like Jenkins, GitLab CI, or similar.
• Infrastructure as Code (IaC) – Managing infrastructure state and automation using Terraform or Ansible.
• Advanced concepts (less common) – Service meshes (like Istio), custom Kubernetes operators, and advanced deployment strategies (canary, blue-green).

Example questions or scenarios:

• "Explain the step-by-step process of what happens within a Kubernetes cluster when a deployment is scaled from one replica to three."
• "How would you design a CI/CD pipeline for a microservice that requires zero-downtime deployments and automated rollback upon failure?"
• "Multiple choice: Which of the following Kubernetes resources is best suited for managing a stateful database application?"

System Protocols and Networking

Given Ericsson's position in the telecommunications industry, networking knowledge is paramount. You will be evaluated on your understanding of how data moves across networks and how systems communicate. A strong performance involves demonstrating a clear grasp of network layers, routing, and security protocols.

Be ready to go over:

• TCP/IP and OSI Models – Understanding the layers of network communication and troubleshooting connectivity issues.
• Network Protocols – Deep knowledge of HTTP/S, DNS, BGP, and TLS/SSL handshakes.
• Security and Firewalls – Configuring secure network boundaries and managing access controls.
• Advanced concepts (less common) – 5G core network architecture, telecom-specific protocols, and edge networking.

Example questions or scenarios:

• "Walk me through the exact sequence of events and protocols used when a user types a URL into their browser until the page loads."
• "How do you troubleshoot a scenario where a Kubernetes pod cannot communicate with an external database?"
• "Multiple choice: Which protocol is primarily responsible for resolving domain names to IP addresses?"

Behavioral and Experience

Ericsson wants to know how you work within a team, how you handle pressure, and what drives your technical decisions. This area is often evaluated by the hiring manager. Strong candidates will provide structured, specific examples of past projects, highlighting their individual contributions and how they navigated challenges.

Be ready to go over:

• Project Deep Dives – Explaining the architecture, challenges, and outcomes of a significant project you previously worked on.
• Conflict Resolution – How you handle disagreements on technical direction with peers or stakeholders.
• Adaptability – Your ability to learn new technologies quickly and pivot when project requirements change.

Example questions or scenarios:

• "Tell me about a time you had to troubleshoot a critical production outage. What was your approach, and what did you learn?"
• "Describe a situation where you had to push back on a developer's request because it violated infrastructure best practices."
• "What are your expectations for this role, and what specific technologies are you most excited to work with at Ericsson?"

As a DevOps Engineer at Ericsson, your day-to-day work will revolve around building, scaling, and securing the infrastructure that powers global telecommunications networks. You will be responsible for designing and maintaining robust CI/CD pipelines that allow software engineering teams to deploy code rapidly and safely. This involves writing extensive automation scripts, managing containerized environments, and ensuring that all deployments adhere to strict security and compliance standards.

Collaboration is a massive part of this role. You will work closely with software developers, quality assurance teams, and network architects to bridge the gap between code creation and production deployment. When an issue arises in production, you will be on the front lines, utilizing your deep knowledge of Linux, networking protocols, and Kubernetes to troubleshoot and resolve bottlenecks. You will also spend significant time optimizing system performance, managing cloud or on-premise resources, and implementing Infrastructure as Code (IaC) to ensure environments are reproducible and consistent.

Furthermore, you will drive strategic initiatives to modernize legacy infrastructure. Ericsson is constantly evolving its 5G and cloud-native offerings, meaning you will frequently evaluate new tools, design proof-of-concepts, and migrate existing services to more efficient, scalable architectures. Your work will directly ensure that Ericsson's platforms remain highly available and performant under massive global traffic loads.