CCIE Routing and Switching Written Exam Guide: What 400-101 Candidates Need to Know
CCIE Routing and Switching Written was the former written qualifying exam for Cisco’s Routing and Switching expert path. Its 400-101 v5.1 version tested whether experienced network professionals could reason about complex enterprise infrastructure, translate requirements into configurations, and troubleshoot interconnected components. The important decision now is not simply how to study: Cisco replaced this path with the CCIE Enterprise Infrastructure route, so candidates must first confirm whether they need historical 400-101 knowledge or the current certification pathway before buying materials or scheduling an exam.
Is CCIE Routing and Switching Written 400-101 still available?
No scheduling decision should begin with an assumption that 400-101 is active. Cisco announced that the CCIE Enterprise Infrastructure qualifying exam would go live on February 24, 2020, replacing the prior CCIE Routing and Switching written-exam path. Cisco also stated that the CCIE Routing and Switching Written v5.0 exam would be replaced by ENCOR 350-401 after that date.
Cisco’s retired-exam policy says retired exams are no longer available for certification or recertification. Certifications earned through retired exams can remain valid until their individual expiration dates, but that does not make the old exam available to new candidates.
For a current certification attempt, use Cisco’s CCIE Enterprise Infrastructure pages to verify the active core-exam and lab requirements. Treat 400-101 study material as historical reference unless Cisco’s official exam information explicitly confirms otherwise. This distinction prevents a common and expensive mistake: preparing for an exam code that cannot be booked.
What should a candidate do before studying?
Start with an official status check, not a practice-question purchase. Confirm the current CCIE Enterprise Infrastructure certification requirements, identify its qualifying core exam, and verify the current registration information through Cisco. If your employer specifically asks for an older Routing and Switching credential, confirm whether it means an existing certification, historical knowledge, or a current replacement pathway.
Do not interpret a page title, search result, or third-party catalogue entry as proof that a retired exam is schedulable. A catalogue can preserve the name of an older credential long after the official testing path has changed. The official retired-exam policy is the authority for availability, while the current certification page is the authority for the replacement direction.
What did the former written exam validate?
The v5.1 written exam validated expertise in configuring, validating, and troubleshooting complex enterprise network infrastructure. It also assessed whether a candidate understood how infrastructure components interoperate and could translate functional requirements into specific device configurations. Those capabilities describe the reasoning standard better than memorizing isolated commands.
A strong historical preparation plan therefore had to connect design intent, protocol behavior, configuration choices, and verification evidence. Knowing a command without understanding its operational effect was not a dependable approach. A candidate needed to ask what requirement a configuration addressed, which neighboring component depended on it, and how a failure would appear in verification output.
This is also why a collection of recalled questions would be a poor substitute for study. The official description points toward applied understanding across a complex system. Memorizing answers cannot establish whether a candidate can select a design, predict interactions, or troubleshoot a fault that is expressed differently from a study example.
What kind of candidate was the exam designed for?
Cisco’s current CCIE Enterprise Infrastructure page states that there are no formal prerequisites, while recommending five to seven years of relevant enterprise-networking experience before taking the exam. That recommendation is useful context for the level of the former written test as well: it was aimed at practitioners who could reason across enterprise infrastructure, not only entry-level learners following isolated configuration recipes.
Formal eligibility and practical readiness are different decisions. A candidate may be allowed to pursue the certification without a prerequisite, yet still need substantial experience to interpret requirements, recognize protocol interactions, and diagnose faults efficiently. Use the experience recommendation as a readiness signal rather than as a claim that Cisco requires a particular employment history.
What did the 400-101 v5.1 format require?
Cisco’s v5.1 topic document described a two-hour test containing 90–110 questions. It was closed book and did not allow outside reference materials. These details matter for historical study because they point to a timed, self-contained reasoning task rather than an open-reference configuration exercise.
A candidate preparing for that format should have practiced making decisions from the information presented in the question. Looking up syntax, searching documentation, or relying on a second screen would not have been part of the stated exam conditions. The practical preparation implication is to use references while learning, then remove them during timed review.
Do not carry these historical format details into a current booking without checking Cisco’s active exam page. Cisco’s expert-level information now describes an online-capable core exam and an eight-hour, in-person, hands-on lab or practical exam for the current expert-level path. That is a different certification structure from the former 400-101 written-only step.
How should the timing information affect study?
Use timed sessions to train prioritization, not to imitate an unsupported current exam format. For historical 400-101 preparation, divide review into short blocks, answer without external references, mark uncertain items, and return to them after completing the first pass. The goal is to preserve reasoning time for questions that require several linked decisions.
Avoid treating the stated question range as a target for guessing how many questions remain on another exam. The 90–110 question count belongs to the v5.1 written exam described by Cisco’s historical topic document and should not be reused as a prediction for the current core exam.
How should the blueprint guide study priorities?
Use the official blueprint as a coverage map, not as a promise of an exact question distribution. Cisco assigned 10% to the Network Principles domain and 13% to the Network Troubleshooting domain in the v5.1 blueprint. Cisco also warned that blueprint topics were general guidelines, that related topics could appear, and that the guidelines could change without notice.
Network Principles deserves a deliberate foundation pass because it supports later configuration and fault analysis. Network Troubleshooting deserves more than a final review because troubleshooting questions require the candidate to connect symptoms with causes and corrective actions. Neither percentage justifies ignoring the remaining blueprint areas, especially when Cisco explicitly described the list as general guidance.
The v5.1 blueprint also included the Evolving Technologies v1.1 domain and applied to written exams scheduled on August 30, 2018, and afterward. That historical scope is important when evaluating old books, notes, or practice material: check which blueprint version they describe before assuming that every topic belongs to the same exam version.
How can a candidate use percentages without overfitting?
Translate each domain percentage into study attention, not a numerical quota of questions. Give every domain an initial learning pass, then allocate additional time to weak areas and high-dependency foundations. For the historical blueprint, keep Network Principles and Network Troubleshooting visible throughout the plan because they support understanding and diagnosis across other areas.
A useful review table has four columns: blueprint domain, concepts you can explain, configurations you can produce, and failures you can diagnose. A topic is not ready merely because it appears in notes. It is stronger when you can state its purpose, predict its interactions, verify the result, and explain what evidence would disprove your first hypothesis.
What is a practical study sequence?
Study in dependency order: establish network principles, build protocol and infrastructure understanding, connect components through configuration reasoning, and then emphasize troubleshooting. This sequence mirrors the skills Cisco described—configuration, validation, troubleshooting, interoperability, and requirement-to-configuration translation—without pretending that a blueprint percentage is a complete curriculum.
First, inventory your knowledge against the historical blueprint rather than beginning with random questions. Separate concepts you have used in production from concepts you recognize only by name. Then build a small, repeatable lab or simulation routine for the areas where you cannot predict behavior. Finally, use timed closed-book sessions to expose gaps in recall and reasoning.
Keep an error log with the original assumption, the evidence you missed, the correct principle, and the verification step that would have found the mistake. This is more useful than recording only a correct answer. Over time, the log should reveal whether your problem is conceptual, configuration-related, verification-related, or simply poor time allocation.
Phase one: establish the foundation
Begin with Network Principles and the relationships that make later troubleshooting possible. For every major concept in your source material, write a short explanation of its purpose, inputs, outputs, and likely failure symptoms. Do not start by copying command syntax; first determine what the network is supposed to accomplish.
Use diagrams to show component boundaries and dependencies. A diagram should help you answer questions such as which device makes a decision, which protocol carries the information, and which verification result confirms that the intended state exists. If your diagram cannot support those answers, it is a drawing exercise rather than a study tool.
Phase two: convert requirements into configurations
Take a functional requirement and work forward to a configuration plan. Identify the required behavior, the components involved, the assumptions that must hold, and the checks that will prove success. Only then write commands. This order develops the translation skill described in Cisco’s exam objectives and reduces dependence on memorized recipes.
After configuring, test both the intended path and a nearby failure condition in a controlled environment. Ask what would happen if an adjacency failed, a route were unavailable, or two components disagreed. The exact lab scenario is your own practice design; it is not a claim about an undisclosed exam task.
Phase three: troubleshoot from evidence
For each fault, begin with scope: identify what works, what fails, and where the boundary of failure lies. Form a small hypothesis, collect the verification evidence that could confirm or reject it, and change one relevant condition at a time. This prevents the common habit of applying several commands before understanding which change solved the problem.
Practice explaining why a symptom follows from a cause. A route absence, an unexpected path, or a failed neighbor relationship should lead to a chain of checks rather than a memorized command list. Finish every exercise by restoring the baseline and documenting the evidence that distinguished the correct diagnosis from plausible alternatives.
How should lab practice support a written exam?
Lab work should strengthen reasoning, not replace it. Use hands-on exercises to observe interoperability, create controlled faults, validate intended states, and connect configuration syntax to behavior. Then close the lab and explain the result from memory. That final explanation is what turns a configuration activity into preparation for a closed-book written assessment.
A compact practice cycle is: define the requirement, draw the relevant components, configure the minimum needed, verify expected behavior, introduce one fault, diagnose it, and record the evidence. Repeat the cycle with a different starting assumption. This develops flexibility without suggesting that any practice scenario reproduces live exam questions.
If your goal has changed to the current CCIE Enterprise Infrastructure certification, lab practice must be aligned with the current official core and practical-exam information rather than the retired 400-101 blueprint. Cisco’s current path includes a hands-on lab or practical exam, so historical written-only preparation is not a complete current-certification plan.
What should a useful lab record contain?
Record the requirement, topology, assumptions, configuration intent, verification commands or observations, failure introduced, diagnosis, correction, and final validation. Include the reason a tempting alternative was rejected. This creates a troubleshooting reference based on cause and evidence instead of a disconnected list of commands.
Keep the record version-specific. Label material as historical 400-101 v5.1 preparation or current CCIE Enterprise Infrastructure preparation. Mixing them without labels can make an old topic list appear current and can cause you to practice the wrong delivery format or exam objective.
Which preparation mistakes waste the most time?
The largest risks are studying the wrong exam, treating the blueprint as a guaranteed question forecast, and using answer memorization in place of technical reasoning. A fourth mistake is postponing troubleshooting until the end. Cisco’s description emphasizes configuration, validation, and troubleshooting, so preparation should exercise all three rather than treating troubleshooting as an optional add-on.
Buying material before confirming status is especially avoidable. The official retired-exam policy and current certification pages should be checked first. If a resource does not identify the blueprint version, exam code, and source of its claims, regard it as unverified until you can reconcile it with Cisco’s information.
Do not use exam dumps, leaked questions, or memorized answer keys as a passing strategy. They cannot establish interoperability understanding or the ability to translate a changing requirement into a defensible configuration. They may also cause you to rehearse obsolete content, particularly for a retired exam.
How can you detect shallow readiness?
Ask yourself to explain a result without looking at notes, then change one condition and predict the new result. If you can repeat a command but cannot explain its purpose, dependencies, or verification evidence, the topic needs more work. Similarly, if you can solve a fault only after seeing the answer, record the missing diagnostic step rather than marking the topic complete.
Use mixed review after learning individual domains. Single-topic drills can create recognition without transfer. A mixed session forces you to identify which principle applies, choose the relevant evidence, and move between configuration and troubleshooting modes—the same kind of integration expected from an expert-level objective.
How should you decide whether you are ready?
Readiness should be based on repeatable performance across the relevant objectives, not on a single high practice score or familiarity with recalled questions. You should be able to explain core principles, derive configurations from requirements, validate intended behavior, and troubleshoot unfamiliar variations without outside references during a timed review.
Before scheduling any current exam, verify the active exam structure and eligibility information with Cisco. For historical 400-101 study, use the v5.1 format only as a closed-book practice constraint: two hours, 90–110 questions, and no outside reference materials. Do not assume those details describe the current core exam.
A final readiness review should include three checks. First, can you identify and repair knowledge gaps from your error log? Second, can you maintain a consistent diagnostic process when the first hypothesis fails? Third, can you explain how related components interact rather than treating each feature as an isolated command set? If any answer is no, refine the plan before booking.
What should happen in the final review period?
Stop expanding the syllabus and consolidate. Revisit the error log, redraw dependency diagrams, rehearse requirement-to-verification workflows, and complete mixed closed-book sessions. Give extra attention to principles that support several domains and to troubleshooting patterns that repeatedly caused incorrect assumptions.
Use official Cisco information for any last-minute status or format check. Do not let an old practice platform, forum post, or catalogue entry decide whether an exam is active. The final administrative check is part of preparation because a technically strong plan is still misdirected if it targets a retired exam.
What is the best next action for a candidate today?
First determine your objective: preserve historical knowledge of CCIE Routing and Switching Written 400-101, or pursue the current CCIE Enterprise Infrastructure certification. If the latter, open Cisco’s current certification and exams-and-training pages and identify the active core and practical requirements. If the former, label every resource as historical v5.1 material and study it for understanding rather than scheduling.
Next, build a one-page gap inventory from the official blueprint. Mark each area as explain, configure, validate, troubleshoot, or unknown. Start with the unknown and dependency-heavy areas, then rotate through mixed practice. Keep Network Principles and Network Troubleshooting explicitly labeled when using the historical percentages: Network Principles was 10%, and Network Troubleshooting was 13%.
Finally, remove any resource that promises certainty through dumps or answer repetition. Choose material that makes its version clear, supports hands-on verification, and helps you reason from requirements and evidence. Recheck Cisco’s official pages before making a booking, because the former 400-101 path was replaced and current certification information is the relevant authority for a new attempt.
A simple decision checklist
Confirm whether your target is historical knowledge or a current Cisco certification. Confirm the official exam status. Confirm the applicable blueprint version. Separate official requirements from your own study preferences. Build configuration and troubleshooting practice around observable evidence. Schedule only after the active Cisco requirements match the plan you have prepared.
This checklist is intentionally short: status, scope, skills, practice, and booking. It keeps the administrative decision in front of the study decision and prevents a familiar exam name from hiding a changed certification path.
Conclusion
CCIE Routing and Switching Written 400-101 remains useful as a historical reference for studying enterprise-network reasoning, but it should not be treated as the current route without official confirmation. Cisco replaced the former path with the CCIE Enterprise Infrastructure structure, which requires a written core exam and a hands-on lab exam. Decide which objective you are pursuing, map study to the correct official blueprint, and practice configuration, validation, interoperability, and troubleshooting as connected skills rather than as memorized answers.
