8x8 India Site Reliability Engineer Interview: Rounds, Questions and Preparation

What the job involves

As a Site Reliability Engineer (SRE) at a global tech company like 8x8 India, you will work at the intersection of software engineering and systems operations to ensure that large-scale, distributed services remain reliable, scalable, and efficient. Day to day, you will monitor production systems, respond to incidents, automate repetitive tasks, and collaborate with development teams to design resilient infrastructure. The role demands a proactive mindset to prevent outages and a passion for solving complex problems under pressure.

Role and Technical Knowledge

1. 1

   What is the difference between a DevOps Engineer and a Site Reliability Engineer?

   Highlight that SRE is a specific implementation of DevOps principles with a focus on reliability, error budgets, and toil reduction, while DevOps is a broader cultural movement. Mention that SREs often have a software engineering background and use SLIs/SLOs to measure reliability.

2. 2

   Explain the concept of an error budget and how it influences decision-making.

   Define error budget as the acceptable amount of downtime or failure (100% minus SLO). Explain that it balances innovation and reliability: if the budget is exhausted, feature releases may be paused to focus on reliability improvements.

3. 3

   What are SLIs, SLOs, and SLAs? Give an example for a video conferencing service.

   SLI is a measured metric (e.g., latency of API calls), SLO is the target (e.g., 99.9% of calls under 200ms), SLA is a contract with consequences. For a video service, an SLI could be call setup success rate, SLO 99.95%, and SLA with refunds if below 99.9%.

4. 4

   How would you approach capacity planning for a service that experiences sudden spikes in traffic?

   Discuss analyzing historical data, forecasting growth, load testing, and using auto-scaling groups. Mention the importance of setting up alerts and having a buffer capacity to handle spikes without degradation.

Practical Scenarios and Troubleshooting

1. 5

   A production server is running out of disk space. How would you troubleshoot and resolve this?

   Outline steps: check disk usage with df and du, identify large files or logs, rotate or delete old logs, and set up log rotation. Also consider moving data to cheaper storage or increasing disk size if needed.

2. 6

   You receive an alert that a website is returning 500 errors. Walk me through your debugging process.

   Start by checking recent changes, then inspect application logs, server metrics (CPU, memory), and database connectivity. Use tools like curl to test endpoints, and consider rolling back if a recent deployment is the cause.

3. 7

   How would you automate the deployment of a microservice to Kubernetes?

   Describe using a CI/CD pipeline (e.g., Jenkins, GitLab CI) to build a Docker image, push to a registry, and update Kubernetes manifests. Mention using Helm charts, rolling updates, and health checks for zero-downtime deployments.

4. 8

   Describe how you would set up monitoring for a web application. What metrics would you track?

   Cover the four golden signals: latency, traffic, errors, and saturation. Mention tools like Prometheus for metrics, Grafana for dashboards, and ELK for logs. Also include alerting thresholds and on-call rotations.

Behavioral and Situational Questions

1. 9

   Tell me about a time you had to troubleshoot a technical problem under pressure. How did you handle it?

   Use the STAR method: describe the situation, task, action (e.g., methodical debugging, communication), and result (e.g., resolved within SLA). Emphasize staying calm and prioritizing impact.

2. 10

   Describe a situation where you had to explain a complex technical issue to a non-technical person.

   Show empathy and clarity: avoid jargon, use analogies, and focus on business impact. Highlight that you confirmed understanding and provided updates.

3. 11

   How do you prioritize tasks when multiple incidents occur simultaneously?

   Explain assessing severity and impact (e.g., customer-facing vs internal), delegating if possible, and communicating with stakeholders. Mention using a triage process and documenting for postmortem.

4. 12

   Give an example of a time you automated a repetitive task. What was the outcome?

   Describe the task, the tool or script used (e.g., Python, Ansible), and the time saved or errors reduced. Highlight the value of reducing toil and improving efficiency.

HR and Company Fit

1. 13

   Why do you want to work as a Site Reliability Engineer, and why at a company like ours?

   Connect your interest in reliability and automation to the company's scale and industry (e.g., cloud communications). Mention specific aspects like handling large-scale systems or innovative culture.

2. 14

   Where do you see yourself in five years?

   Show ambition aligned with SRE growth: deepening expertise in cloud-native technologies, taking on more responsibility, or moving into a lead SRE role. Avoid saying you want to leave the company.

3. 15

   How do you handle working in a 24/7 on-call rotation?

   Demonstrate awareness of the demands and your ability to manage stress, maintain work-life balance, and follow escalation procedures. Mention past experiences with responsibility and teamwork.

4. 16

   What are your salary expectations?

   Research typical fresher SRE salaries in India (e.g., 6-12 LPA for global tech). Provide a range based on company size and location, and express flexibility and interest in the overall opportunity.