20 Observability Interview Questions and Answers

Observability is a practice in which system data is collected and analyzed in order to identify issues and optimize performance. This data can come from a variety of sources, including system logs, application performance data, and user feedback. As a result, observability is a critical skill for any DevOps engineer or site reliability engineer.

In this article, we will review some common observability interview questions and how you can answer them. We will also discuss what interviewer are looking for when they ask these questions.

Observability Interview Questions and Answers

Here are 20 commonly asked Observability interview questions and answers to prepare you for your interview:

1. What is observability?

Observability is a measure of how well a system can be monitored and understood. It is a key metric for determining the health of a system and whether or not it is functioning properly.

2. Can you explain the difference between monitoring and observability?

Monitoring is the process of collecting data from a system in order to track its performance and identify any issues. Observability is the process of using that data to understand what is happening inside the system and why.

3. How are metrics, events, traces, and logs different from each other?

Metrics are numerical values that are tracked over time in order to measure some aspect of a system. Events are discrete occurrences that happen at a particular point in time, and can be used to trigger alerts or actions. Traces are sequences of events that happen over time, and can be used to debug issues or track performance. Logs are records of events that are written to a file or database, and can be used for auditing or debugging.

4. What do you understand by GELF and Graylog Extended Log Format?

GELF is the Graylog Extended Log Format, which is a log format that is optimized for streaming and processing large amounts of log data. It is designed to be efficient and easy to parse, and it supports a variety of features that make it well-suited for use in a distributed logging system.

5. What’s the difference between differential privacy and statistical databases?

Differential privacy is a newer concept that is gaining popularity due to its stronger privacy guarantees. In a nutshell, differential privacy ensures that no individual record in a dataset can be uniquely identified. This is in contrast to statistical databases, which do not provide any privacy guarantees.

6. What are some common open source tools used for generating metrics?

Some common open source tools used for generating metrics are Statsd, Prometheus, and Graphite.

7. What is Prometheus?

Prometheus is an open-source monitoring system that was originally developed by SoundCloud. It is now a part of the Cloud Native Computing Foundation. Prometheus is often used in conjunction with Kubernetes and is known for its ease of use and powerful data model.

8. What are the best practices for implementing security in a Kubernetes cluster?

There are a few different best practices for implementing security in a Kubernetes cluster. Firstly, it is important to make sure that all of the nodes in the cluster are properly secured. This means ensuring that only authorized users have access to the nodes, and that all of the nodes are properly configured to prevent unauthorized access.

Another best practice is to make sure that all of the containers in the cluster are properly secured. This means ensuring that all of the containers are properly configured to prevent unauthorized access, and that all of the data inside of the containers is properly secured.

Finally, it is important to make sure that the Kubernetes API is properly secured. This means ensuring that only authorized users have access to the API, and that all of the API calls are properly authenticated.

9. What do you know about OAuth 2.0, OpenID Connect, and JWT?

OAuth 2.0 is an authorization protocol that allows users to grant third-party applications access to their data without sharing their credentials. OpenID Connect is an authentication protocol that builds on top of OAuth 2.0 and allows users to authenticate with their existing credentials from a variety of providers. JWT is a standard for encoding and transmitting data in JSON format that can be used with both OAuth 2.0 and OpenID Connect.

10. What are some good ways to implement authentication in a microservices architecture?

There are a few different ways to implement authentication in a microservices architecture. One way is to use a shared authentication service that all microservices can communicate with. Another way is to use an API gateway that can act as an intermediary between clients and microservices. Finally, you can also implement authentication directly into each microservice.

11. What are sidecars? When should they be used?

Sidecars are additional processes that are deployed alongside the main application process in order to provide monitoring and logging functionality. They are often used in microservices architectures in order to provide a centralized way to collect data from all of the different services.

12. What’s your understanding of Multi-tenancy?

Multi-tenancy is a software architecture where a single instance of a software application serves multiple tenants. A tenant is a group of users who share a common access with specific privileges to the software instance.

13. Why is multi-tenancy important?

Multi-tenancy is important because it allows for the efficient use of resources. When multiple tenants share the same infrastructure, it reduces the overall cost of ownership. In addition, it makes it easier to manage and monitor the system as a whole, since there are fewer individual components to keep track of.

14. What is active directory?

Active Directory is a Microsoft technology used to manage network resources. It is a hierarchical database that stores information about objects on a network, such as users, computers, and groups. Active Directory can be used to provide security and access control for a network.

15. What is LDAP?

LDAP is the Lightweight Directory Access Protocol. It is a protocol used to access directory services, and it is often used to store information about users and resources in a network.

16. What are the differences between SAML and OAuth?

SAML (Security Assertion Markup Language) and OAuth (Open Authorization) are both open standards for authentication and authorization. SAML is typically used by enterprises for single sign-on (SSO), while OAuth is used by web and mobile applications for API authentication and authorization. The main difference between the two is that SAML is an XML-based standard, while OAuth is a JSON-based standard.

17. What are the advantages of using a service mesh like Istio?

Istio is a popular service mesh that can provide a number of advantages for those looking to improve the observability of their microservices. Istio can automatically generate detailed traffic logs, which can be extremely helpful in understanding how microservices are communicating with one another. Istio can also provide fine-grained control over traffic routing, which can be useful in A/B testing or canary deployments.

18. What is a honeypot? How does it work?

A honeypot is a system that is designed to attract and detect malicious activity. It is usually deployed in a production environment and works by masquerading as a production system. When a honeypot is attacked, it can provide information about the attacker, their methods, and their goals. This information can be used to improve security defenses.

19. What is an XSS attack?

An XSS attack is a type of attack where a malicious user tries to inject code into a web page in order to execute it on the user’s machine. This can be used to steal information or to simply redirect the user to a different page.

20. What is DDoS? Can you give me some examples of DDoS attacks that have happened recently?

DDoS stands for Distributed Denial of Service. This is a type of attack where the attacker attempts to overload a system with requests, so that legitimate users are unable to access the system. This can be done by flooding the system with requests from multiple computers, or by using a botnet to send a large number of requests. Some recent examples of DDoS attacks include the attacks on Github in 2018, and the attacks on DynDNS in 2016.