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Arista Networks Interview Questions

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Suppose there exists a new airline named Jetco that flies domestically across North America. Jetco recently had a study commissioned that tested the boarding time of every airline, and it came out that Jetco had the fastest average boarding times of any airline.

What factors could have biased this result, and what would you look into?

What could potentially bias the average boarding time in favor of an airline that only flies domestically?

What could potentially bias the average boarding time in favor of an airline that only flies domestically?

Boarding Times Bias

A new airline came out as the fastest average boarding times compared to other airlines.  What factors could have biased this result and what would you look into?

Statistics

Let’s say you work for a social media company that has just done a launch in a new city. Looking at weekly metrics, you see a slow decrease in the average number of comments per user from January to March in this city.

The company has been consistently growing new users in the city from January to March.

What are some reasons why the average number of comments per user would be decreasing and what metrics would you look into?

What metric could be used to measure if active users are still engaging on the platform despite an overall decrease in the average number of comments per user?

What metric could be used to measure if active users are still engaging on the platform despite an overall decrease in the average number of comments per user?

Decreasing Comments

How would you investigate a decline in the average number of comments per user?

Product Sense & Metrics

Let’s say that your company is running a standard control and variant AB test on a feature to increase conversion rates on the landing page. The PM checks the results and finds a .04 p-value.

How would you assess the validity of the result?

Experiment Validity

A/B Testing

Arista Networks Salaries by Position

<h3>Job Description</h3><div>Job Description<div>Company Description Arista Networks is an industry leader in data-driven, client-to-cloud networking for large data center, campus and routing environments. What sets us apart is our relentless pursuit of innovation. We leverage the latest advancements in cloud computing, artificial intelligence, and software-defined networking to provide our clients with a competitive edge in an increasingly interconnected world. Our solutions are designed to not only meet the current demands of the digital landscape but to also anticipate and adapt to future challenges.At Arista we value the diversity of thought and perspectives that each employee brings to the table. We  believe that fostering an inclusive environment, where individuals from various backgrounds and experiences feel welcome, is essential for driving creativity and innovation.Our commitment to excellence has earned us several prestigious awards, such as Best Engineering Team, Best Company for Diversity, Compensation, and Work-Life Balance. At Arista, we take pride in our track record of success and strive to maintain the highest standards of quality and performance in everything we do.Job Description Who You’ll Work WithArista Networks is looking for world-class software engineers to join our Extensible Operating System (EOS) software development team. As a core member of the EOS team, you will be part of a fast-paced, high caliber team-building features to run the world's largest data center networks. Your software will be a key component of Arista's EOS, Arista's unique, Linux-based network operating system that runs on all of Arista's data center networking products.The EOS team is responsible for all aspects of the development and delivery of software meant to run on the various Arista switches. You will work with your fellow engineers and members of the marketing team to gather and understand the functional and technical requirements for upcoming projects. You will help write functional specifications, design specifications, test plans, and the code to bring all of these to life. You will also work with customers to triage and fix problems in their networks. Internally, you will develop automated tests for your software, monitor the execution of those tests, and triage and fix problems found by your tests. At Arista, you will own your projects from definition to deployment, and you will be responsible for the quality of everything you deliver.What You’ll DoThis role demands strong and broad software engineering fundamentals, and ideally a good understanding of networking including capabilities like L2, L3, and fundamentals of commercial switching HW. Your role will not be limited to a single aspect of EOS at Arista, but cover all aspects of EOS.Responsibilities:<ul><li>Write functional specifications and design specifications for features related to forwarding traffic on the internet and cloud data centers.</li><li>Independently implement solutions to small-sized problems in our EOS software, using the C and C++ programming languages.</li><li>Write test plan specifications for small-sized features in EOS, and implement automated test programs to execute the cases described in the test plan.</li><li>Debug problems found by our automated test programs and fix the problems. </li><li>Work on a team implementing, testing, and debugging solutions to larger routing protocol problems.</li><li>Worth with Customer Support Engineers to analyze problems in customer networks and provide fixes for those problems when needed in the form of new software releases or software patches.</li><li>Work with the System Test Engineers to analyze problems found in their tests and provide fixes for those problems.</li><li>Mentor new and junior engineers to bring them up to speed in Arista’s software development environment.</li><li>Review and contribute to the specifications and implementations written by other team members.</li><li>Help to create a schedule for the implementation and debugging tasks, update that schedule weekly, and report it to the project lead.</li></ul>Qualifications <ul><li>BSc, MS or Ph.D. in Computer Science/Electrical Engineering/Computer Engineering with 3+ years of related post graduate work experience</li><li>Knowledge of C and/or C++.</li><li>Knowledge of UNIX or Linux.</li><li>Understanding of L2/L3 networking including at least one of the following areas is desirable:</li><li>IP routing protocols, such as RIP, OSPF, BGP, IS-IS, or PIM.</li><li>Layer 2 features such as 802.1d bridging, the 802.1d Spanning Tree Protocol, the 802.1ax Link Aggregation Control Protocol, the 802.1AB Link Layer Discovery Protocol, or RFC 1812 IP routing.</li><li>Ability to utilize, test, and debug packet forwarding engine and a hardware component’s vendor provided software libraries in your solutions.</li><li>Infrastructure functions related to distributed systems such as messaging, signalling, databases, and command line interface techniques.</li><li>Hands on experience in the design and development of ethernet bridging or routing related software or distributed systems software is desirable.</li><li>Hands on experience with enterprise or service provider class Ethernet switch/router system software development, or significant PhD level research in the area of network routing and packet forwarding.</li><li>Applied understanding of software engineering principles.</li><li>Strong problem solving and software troubleshooting skills.</li><li>Ability to design a solution to a small-sized problem, and implement that solution without outside help. Able to work on a small team solving a medium-sized problem with limited oversight.</li></ul>Compensation InformationThe new hire base pay for this role has a salary range of $123,000 to $191,000. Arista offers different pay ranges based on work location, so that we can offer consistent and competitive pay appropriate to the market. The actual base pay offered will be based on a wide range of factors, including skills, qualifications, relevant experience, and work location. The pay range provided reflects base pay only and in addition certain roles may also be eligible for discretionary Arista bonuses and equity. Employees in Sales roles are eligible to participate in Arista’s Sales Incentive Plan, which pays commissions calculated as a percentage of eligible sales. US-based employees are also entitled to benefits including medical, dental, vision, wellbeing, tax savings and income protection. The recruiting team can share more details during the hiring process specific to the role and location.#LI-SZ1This is a mid-level software engineer requirement not applicable for fresh graduates or interns. Additional Information <div></div>Arista Networks is an equal opportunity employer.  Arista makes all hiring and employment-related decisions in a non-discriminatory manner without regard to race, color, religion, sex, sexual orientation, gender identity, national origin or any other factor determined to be unlawful under applicable federal, state, or law law.  All your information will be kept confidential according to EEO guidelines.</div></div>

Arista Networks is the leader in software driven networking solutions for today’s largest Data Center (DC), Cloud, Internet/WAN, Service Provider (SP) and Campus environments. Arista has over 7500 customers ranging from the largest cloud providers, to healthcare, government, carrier, finance, education, and production web/SaaS companies. Arista's products are the foundation underpinning much of modern society's operations. Arista has ambitious plans and an unprecedented opportunity for growth and we are looking for many more engineers and designers to join us in building and innovating the world's networks. Arista is a profitable, publicly quoted company with revenues of over $8B with a culture of invention, quality, respect, and fun. As a Software Engineer your core responsibility is to deliver new product features. A major part of this is writing and owning the code that drives our products. However, the role of a Software Engineer is much bigger than ‘simply’ writing code. Software engineers work on the whole development process, including:<ul><li>Suggesting and deciding what features to build</li><li>Driving the design and architecture</li><li>Pushing, testing, documenting the feature</li><li>Working alongside customers in the field if needed</li></ul>Are you right for this role? This is an interesting and exciting opportunity to be a part of the software team that is redefining Data Centre switching. For success at Arista all you need is:<ul><li>Strong engineering and Computer Science fundamentals with 4-10 years of industry experience.</li><li>Extensive background in algorithms and strong software architecture skills</li><li>Fluency in one of C/C++/Python programming</li><li>Hands-on experience with designs and implementations in a strong product-engineering environment</li><li>Strong communication skills and the ability to work in a team environment</li><li>Experience working through the complete software development life cycle right from</li><li>requirements gathering to delivering the fully developed feature.</li></ul> Preferred qualifications (Any one of the below):<ul><li>Strong software debugging skills especially in embedded systems.</li><li>Experience with software development for the forwarding ASICs, FPGAs, Network Processors etc</li><li>Experience with DPDK, software forwarding, Qos, Layer 2 protocols like 802.1X, AAA, Macsec etc.</li><li>Experience with hardware abstraction layer</li><li>Experience in Network Systems Software development is a plus</li></ul>

Cloud EOS Team· Arista Networks is the leader in building software driven cloud networks for today’s datacenter, cloud and campus environments. Arista delivers the most efficient, reliable and high performance Universal Cloud Network architectures based on 10G, 25G, 40G, 50G, 100G and 400G platforms delivered with an extensible operating system – Arista EOS®. Arista EOS is built on an open, programmable, and resilient state-sharing architecture that delivers maximum system uptime, reduces CAPEX and OPEX by simplifying IT operations and enables business agility.· We are building disruptive products and services that deliver highly automated networks that interconnect and secure connectivity between various global locations. As a part of the team you will be exposed to wide variety of technologies like EOS (Extensible Operating System), multithreaded, multicore software forwarding based on DPDK, public cloud (AWS, Azure, GCP) infrastructure, Path selection, NFV, Containers, Network Segmentation, Virtualization, microservice based architectures, CI/CD pipelines, and Terraform-based declarative provisioning models. As a core member of the CloudEOS team, you will be part of a fast paced, high-caliber team building cutting edge software products for Cloud-enabled WAN connectivity. The team is responsible for all aspects of the development and delivery of control plane, software data plane, and management platform/APIs/services.· Arista provides an open Engineering-driven culture which fosters innovation and enables engineers to Learn, Lead and Thrive. Our adoption of modern software tools, methodologies and processes and emphasis on automation enables our engineers to focus their energies on the truly complex problems and be among the most productive in the industry. Arista's products are purpose built with the scale, performance and quality required to operate in some of the most demanding environments - this provides engineers the platform and rigour to learn and gain experience in building complex, scalable software systems.Basic qualifications· Bachelor's/Master's degree in Engineering· 3+ years of experience working as a Systems Software Development Engineer· Proficiency in C++/C programming language· Software Development experience with LinuxPreferred qualifications· Experience with DPDK, Software Forwarding, Qos.· Python and/or Golang development experience· Strong communication skills and the ability to work in a team environment· Experience working through the complete software development life cycle right from requirements gathering to delivering the fully developed feature.· Strong software debugging skills especially in embedded systems.· Experience in Network Systems Software development is a plus

Arista Networks is an industry leader in data-driven, client-to-cloud networking for large data center, campus and routing environments. Arista is a well-established and profitable company with over $5 billion in revenue. Arista’s award-winning platforms, ranging in Ethernet speeds up to 800G bits per second, redefine scalability, agility, and resilience. Arista is a founding member of the Ultra Ethernet consortium. We have shipped over 20 million cloud networking ports worldwide with CloudVision and EOS, an advanced network operating system. Arista is committed to open standards, and its products are available worldwide directly and through partners.At Arista, we value the diversity of thought and perspectives each employee brings. We believe fostering an inclusive environment where individuals from various backgrounds and experiences feel welcome is essential for driving creativity and innovation.Our commitment to excellence has earned us several prestigious awards, such as the Great Place to Work Survey for Best Engineering Team and Best Company for Diversity, Compensation, and Work-Life Balance. At Arista, we take pride in our track record of success and strive to maintain the highest quality and performance standards in everything we do. Who You’ll Work WithAs a software engineer at Arista, you own your project end to end. You and your project team will work with product management and customers to define the requirements and design the architecture. You’ll build the backend, write automated tests, and get it deployed into production via our CD pipeline. As a senior member of the team you’ll also be expected to help mentor and grow new team members. This role demands a strong and broad software engineering background, and you won’t be limited to any single aspect of the product or development process.The candidate will be working with the WiFi team at Arista, developing cutting edge and next generation WiFi solutions in a fast-paced environment. The WiFi team is responsible for the end to end development of the Cloud managed WiFi product portfolio of Arista. This specific position is for the WiFi AccessPoint team. What You’ll DoAs a core member of the AccessPoint team, the candidate is expected to work closely with relevant teams to understand product requirements, design the solution, build the software and deliver it for final validation and customer deployment. The successful candidate will also keep track of new and emerging technologies and their impact on Arista products, come up with new and innovative ideas to improve and differentiate the product and help Arista become a leading player in the Campus space. The candidate will also work closely with sales and support teams to push new solutions, understand customer needs and pain points and help resolve escalations. The candidate is expected to have a strong background in software development and good understanding of systems and networking areas with the knowledge of the WiFi area as an added bonus.The candidate's role will not be limited to a single aspect of the product, it will be broad encompassing many different aspects including but not limited to developing new Access Points, designing and implementing new features, tracking new technologies and working closely with the sales and customer teams. Requirements:• Strong engineering and Computer Science fundamentals• Minimum 3-15 years of relevant experience• Well versed with programming in one of C/C++ languages• Experience working in a Linux environment, developing applications or Linux drivers Proven experience in Any of the below:1. Network device drivers, operating system internals, Kernels, compilers, SOC architecture2. User space development for connectivity related products (Wireless Lan access points/ controllers, networking equipment) in one or more of following areas: • HostAPD, Portal, RADIUS, AAA, Identity and role management, Radsec • Tunnels, Firewall, Iptables, Flow Classification, QoS, TLS, DTLS Preferred Skills:• Experience with Wi-Fi device drivers on Linux.• Hands-on experience in working with one or more WIFI chipset platforms• Good System Level understanding of the Wireless AP functionality• Experience in developing Wi-Fi features, system integration, evaluate various performance parameters

Company DescriptionArista Networks is an industry leader in data-driven, client-to-cloud networking for large data center, campus and routing environments. Arista is a well-established and profitable company with over $8 billion in revenue. Arista’s award-winning platforms, ranging in Ethernet speeds up to 800G bits per second, redefine scalability, agility, and resilience. Arista is a founding member of the Ultra Ethernet consortium. We have shipped over 20 million cloud networking ports worldwide with CloudVision and EOS, an advanced network operating system. Arista is committed to open standards, and its products are available worldwide directly and through partners.At Arista, we value the diversity of thought and perspectives each employee brings. We believe fostering an inclusive environment where individuals from various backgrounds and experiences feel welcome is essential for driving creativity and innovation.Our commitment to excellence has earned us several prestigious awards, such as the Great Place to Work Survey for Best Engineering Team and Best Company for Diversity, Compensation, and Work-Life Balance. At Arista, we take pride in our track record of success and strive to maintain the highest quality and performance standards in everything we do.Job DescriptionWho You’ll Work WithThe EOS Routing PI team is responsible for developing routing protocols like BGP, OSPF and ISIS and Data Center and SP technologies like MPLS, Segment Routing and EVPN. A unique feature of the Arista routing team is that the routing software is common across Campus, Data Center and Service Provider routing features. This is a global team that spreads multiple geographies working on cutting edge features that get deployed in the largest Cloud titan, Service Provider, Enterprise and Campus networks.What You’ll Do<ul><li>Write functional specifications and design specifications for small-sized routing protocol features.</li><li>Independently implement solutions to small-sized problems in our routing protocol software, using the C, C++, and python programming languages.</li><li>Write test plan specifications for small-sized routing protocol features, and implement automated test programs to execute the cases described in the test plan.</li><li>Debug problems found by our automated test programs and fix the problems.</li><li>Work on a team implementing, testing, and debugging solutions to larger routing protocol problems.</li></ul>Qualifications<ul><li>B.E./ M.E., MS or Ph.D. in Computer Science/Electrical Engineering/Computer Engineering with 3-10 years of related work experience</li><li>Knowledge of C or C++</li><li>Knowledge of UNIX or Linux</li><li>Understanding of IP networking and IP routing protocols, specifically one of RIP, OSPF, BGP, IS-IS, or PIM.</li><li>Hands on experience in the design and development of IP routing protocol or distributed systems software.</li><li>Hands on experience with enterprise or service provider class, ethernet switch/router system software development, or significant PhD level research in the area of network routing and packet forwarding.</li><li>Applied understanding of software engineering principles</li><li>Strong problem solving and software troubleshooting skills.</li><li>Ability to design a solution to a small-sized problem, and implement that solution without outside help. Able to work on a small team solving a medium-sized problem with limited oversight.</li></ul>Additional InformationArista stands out as an engineering-centric company. Our leadership, including founders and engineering managers, are all engineers who understand sound software engineering principles and the importance of doing things right.We hire globally into our diverse team. At Arista, engineers have complete ownership of their projects. Our management structure is flat and streamlined, and software engineering is led by those who understand it best. We prioritize the development and utilization of test automation tools.Our engineers have access to every part of the company, providing opportunities to work across various domains. Arista is headquartered in Santa Clara, California, with development offices in Australia, Canada, India, Ireland, and the US. We consider all our R&D centers equal in stature.<ul><li>Join us to shape the future of networking and be part of a culture that values invention, quality, respect, and fun.</li></ul>

Company DescriptionArista Networks is an industry leader in data-driven, client-to-cloud networking for large data center, campus and routing environments. Arista is a well-established and profitable company with over $8 billion in revenue. Arista’s award-winning platforms, ranging in Ethernet speeds up to 800G bits per second, redefine scalability, agility, and resilience. Arista is a founding member of the Ultra Ethernet consortium. We have shipped over 20 million cloud networking ports worldwide with CloudVision and EOS, an advanced network operating system. Arista is committed to open standards, and its products are available worldwide directly and through partners.At Arista, we value the diversity of thought and perspectives each employee brings. We believe fostering an inclusive environment where individuals from various backgrounds and experiences feel welcome is essential for driving creativity and innovation.Our commitment to excellence has earned us several prestigious awards, such as the Great Place to Work Survey for Best Engineering Team and Best Company for Diversity, Compensation, and Work-Life Balance. At Arista, we take pride in our track record of success and strive to maintain the highest quality and performance standards in everything we do. Job DescriptionWho You’ll Work WithCloudVision is Arista’s enterprise network management and streaming telemetry SaaS offering, serving the world’s largest Financials, Media and Entertainment, Health Care, and Cloud companies. As we continue to scale the service and expand into new markets, we’re looking to grow the team with experienced Software Engineers anchored by our Bangalore and Pune team.CloudVision’s core infrastructure is a scale-out distributed system providing real-time and historical access to the full network state, along with frameworks for building advanced analytics. It’s written in Go and leverages open source technologies like HBase, ClickHouse, ElasticSearch, and Kafka under the covers. We’re constantly investing in scaling out the platform and building richer analytics capabilities in the infrastructure.On top of this core platform, we are building network management and analytics applications to fully automate today’s enterprise network, from CI/CD pipelines for network automation to advanced analytics and remediation for network assurance.What You’ll DoAs a backend software engineer at Arista, you own your project end-to-end. You and your project team will work with product management and customers to define the requirements and design the architecture. You’ll build the backend, write automated tests, and get it deployed into production via our CD pipeline. As a senior member of the team, you’ll also be expected to help mentor and grow new team members. This role demands a strong and broad software engineering background, and you won’t be limited to any single aspect of the product or development process.Qualifications<ul><li>BS/MS degree in Computer Science and 4+ years of relevant experience.</li><li>Strong knowledge of one or more programming languages (Go, Python, Java)</li><li>Experience developing distributed systems or scaling out applications for a SaaS environment</li><li>Experience developing scalable backend systems in Go is a plus</li><li>Experience with network monitoring, network protocols, machine learning or data analytics is a plus</li></ul>Additional InformationArista stands out as an engineering-centric company. Our leadership, including founders and engineering managers, are all engineers who understand sound software engineering principles and the importance of doing things right.We hire globally into our diverse team. At Arista, engineers have complete ownership of their projects. Our management structure is flat and streamlined, and software engineering is led by those who understand it best. We prioritize the development and utilization of test automation tools.Our engineers have access to every part of the company, providing opportunities to work across various domains. Arista is headquartered in Santa Clara, California, with development offices in Australia, Canada, India, Ireland, and the US. We consider all our R&D centers equal in stature.Join us to shape the future of networking and be part of a culture that values invention, quality, respect, and fun.

Question	Topic	Difficulty	Ask Chance
Boarding Times Bias	Statistics	Medium	Very High
Decreasing Comments	Product Sense & Metrics	Easy	Very High
Experiment Validity	A/B Testing	Medium	Very High

Arista Networks Interview Questions

Arista Networks Interview Guides

Arista Networks Interview Questions

Arista Networks Salaries by Position

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