Arista Networks interview process (2026)

Round-by-round breakdown of the Arista Networks software engineering interview across 3 levels and 13 rounds: interview mode, sample questions, and worked solutions.

Arista Networks salary & ratings · All interview processes

Software Engineer (New Grad / Campus)

Difficulty: Hard · Timeline: ~2-4 weeks · Recommended prep: 8-10 weeks · Cooldown: ~6 months

  1. Round 0: HackerRank Online Assessment

    Assessment · ~90 min · difficulty 3/5 · elimination round

    Mode of interview: Online assessment · HackerRank

    Sample question: Shortest path in a grid — given an R x C grid of 0s and 1s (1 = obstacle), print the minimum number of 4-directional moves from the top-left to the bottom-right cell, or -1 if unreachable. Input: R C, then the grid rows. Reported in Arista's campus OA as a BFS-with-obstacles problem.

  2. Round 1: Technical Interview 1 — DSA from scratch in C/C++

    Onsite · ~60 min · difficulty 4/5 · elimination round

    Mode of interview: Onsite or virtual onsite interview

    Sample question: Reverse a singly linked list in groups of k — define the node struct yourself, build the list from input, and reverse every group of k nodes in place using only raw pointers (no STL). Input: n k, then n values; print the resulting list. It is highly probable you get one linked-list or tree question in this round.

  3. Round 2: Technical Interview 2 — C/C++ internals, memory and OS

    Onsite · ~60 min · difficulty 4/5 · elimination round

    Mode of interview: Onsite or virtual onsite interview

    Sample question: Implement my_printf(const char* fmt, ...) using <cstdarg> supporting %d, %s and %c, writing characters with putchar only. Follow-ups: what does int *x[10] declare vs int (*x)[10]; why can sizeof a struct exceed the sum of its members; how does the struct hack / flexible array member work?

  4. Round 3: Technical + HR wrap-up

    Behavioral · ~60 min · difficulty 2/5

    Mode of interview: Live behavioral interview

Software Engineer (Experienced, 3-6 yrs)

Difficulty: Hard · Timeline: ~2-4 weeks · Recommended prep: 6-8 weeks · Cooldown: ~6 months

  1. Round 0: Recruiter screen

    Phone · ~30 min

    Mode of interview: Remote phone or video interview

  2. Round 1: Coding round — 3 problems, live C++ on CoderPad

    Onsite · ~60-75 min · difficulty 4/5 · elimination round

    Mode of interview: Live interview · CoderPad

    Sample question: Design a stack supporting push, pop, top and getMin all in O(1) — implement it from scratch in C++ without STL containers (write your own linked node struct), then process q operations read from stdin and print answers for top and min queries (print "empty" when the stack is empty).

  3. Round 2: C/C++ internals and OS deep dive

    Onsite · ~60 min · difficulty 5/5 · elimination round

    Mode of interview: Onsite or virtual onsite interview

    Sample question: Implement an LRU cache from scratch: doubly linked list plus your own hash table (no std::unordered_map), get and put in O(1). Follow-ups: how would you implement std::vector in C — growth factor, realloc vs malloc+memcpy, amortised cost — and when does test-and-set beat a mutex on a multiprocessor?

  4. Round 3: Networking / systems round with live C debugging

    System_design · ~90-120 min · difficulty 4/5 · elimination round

    Mode of interview: Live system design interview

    Sample question: On one Linux machine, use network namespaces and veth pairs to build a 3-hop topology and make end-to-end ping work. Then walk a packet through a switch: L2 MAC lookup, VLAN handling, L3 route lookup, TCAM/ACL processing and MAC rewrite — where does each step run in hardware vs software?

  5. Round 4: Hiring manager round

    Behavioral · ~45-60 min · difficulty 2/5

    Mode of interview: Live behavioral interview

Senior Software Engineer

Difficulty: Hard · Timeline: ~1-2 weeks · Recommended prep: 4-6 weeks · Cooldown: ~6 months

  1. Round 0: Recruiter screen

    Phone · ~20 min

    Mode of interview: Remote phone or video interview

  2. Round 1: Coding + fundamentals with a senior engineer

    Onsite · ~60 min · difficulty 4/5 · elimination round

    Mode of interview: Onsite or virtual onsite interview

    Sample question: Reverse a singly linked list in groups whose sizes follow the Fibonacci sequence (groups of 1, 1, 2, 3, 5, ...), in place with raw pointers and no STL. Follow-ups: what does volatile actually guarantee, when do atomics with CAS beat a mutex, and how do you write a thread-safe singleton?

  3. Round 2: Systems design with the engineering manager

    System_design · ~60-90 min · difficulty 4/5 · elimination round

    Mode of interview: Live system design interview

    Sample question: Design the backend of an email/messaging system at the process level: on-disk storage layout, delivery pipeline, retry and failure handling, and how concurrent readers/writers stay safe on a multiprocessor. Then: sketch a CLI tool that filters a large log file with a regex — what are its memory and I/O characteristics?

  4. Round 3: Director conversation + fit

    Behavioral · ~45 min · difficulty 2/5

    Mode of interview: Live behavioral interview

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Worked sample solutions (code, design diagrams, and STAR answers) for every round are available in the FAANGPlus app: open interview processes.