Timed CCNA Practice Tests with Detailed Explanations (2026 Update)

CCNA Practice Tests by Topic: Subnetting, Routing, Switching & Security

Passing the CCNA requires both conceptual understanding and practical exam readiness. Structured practice tests focused by topic help target weaknesses efficiently and build confidence. Below is a concise, actionable guide to topic-specific practice tests for Subnetting, Routing, Switching, and Security — including what to test, question types, example problems, and a 4-week study plan.

Why topic-based practice tests

• Focus: Isolate weak areas without redoing entire exams.
• Progress tracking: Measure improvement per domain.
• Efficiency: Spend time learning instead of re-sitting full-length tests repeatedly.

Test design by topic

Subnetting

• Purpose: Master IPv4/IPv6 addressing, masks, VLSM, and subnet math speed.
• Question types:
  • Binary conversions (IP ↔ binary)
  • Calculate network, broadcast, host ranges
  • Create subnets from given prefix and host requirements (VLSM)
  • IPv6 prefix and address types
• Example problems:
  1. Given 192.168.10.0/24, create 6 subnets that each support at least 20 hosts — provide network addresses and masks.
  2. Convert 172.16.5.130 to binary and identify its subnet for /26.
  3. For IPv6 global unicast 2001:db8::/48, assign /64 subnets for four departments.
• Scoring & timing: 15–20 questions, 20–30 minutes. Aim for 90%+ accuracy.

Routing

• Purpose: Verify understanding of static routing, OSPF (single-area), EIGRP basics, route summarization, and redistribution concepts.
• Question types:
  • Configuration snippets and expected routing table outcomes
  • Path selection scenarios with metrics
  • OSPF LSDB and LSA role identification
  • Troubleshooting routed networks (connectivity and missing routes)
• Example problems:
  1. Given three routers with static routes, determine the routing table entries after adding a summary route.
  2. Interpret OSPF neighbor states and identify why adjacency fails (mismatched MTU, area type).
  3. Choose the best path given cost/metric differences between OSPF and EIGRP.
• Scoring & timing: 15 questions, 25–35 minutes. Target 85%+.

Switching

• Purpose: Test VLANs, trunking (802.1Q), STP (RSTP), EtherChannel, and port security.
• Question types:
  • VLAN assignment and inter-VLAN routing scenarios
  • Trunk negotiation and native VLAN issues
  • STP convergence and root bridge calculations
  • Troubleshooting switchport configurations
• Example problems:
  1. Configure trunking for two switches with VLANs 10, 20, 30; explain native VLAN implications.
  2. Given a network of four switches, determine the STP root bridge and blocked ports.
  3. Identify why PC in VLAN 20 can’t reach default gateway — port in wrong VLAN or trunk misconfig?
• Scoring & timing: 15–20 questions, 25–30 minutes. Aim for 90%.

Security

• Purpose: Assess network device security fundamentals: ACLs, device hardening, basic VPN concepts, and Layer ⁄₃ security features.
• Question types:
  • ACL creation and matching behavior (standard vs extended)
  • Device management security (SSH, password encryption, AAA basics)
  • Basic VPN, NAT, and firewall rule interpretation
  • Mitigations: DHCP snooping, DAI, port security consequences
• Example problems:
  1. Write an extended ACL to permit HTTP from 10.0.0.0/24 to 192.168.1.0/24 but deny all else.
  2. Explain why SSH fails with “no matching key exchange” — what commands fix it?
  3. Given a switch config with DHCP snooping enabled, identify why hosts are denied leases.
• Scoring & timing: 12–18 questions, 20–30 minutes. Target 90%.

Mixed-topic mini test

• Purpose: Simulate exam-like context switching.
• Structure: 40 questions across all four topics, 75 minutes, weighted to CCNA blueprint (subnetting, switching, routing, security emphasis).
• Passing target: 80%+ for readiness.

4-week practice plan (assumes ~10 hours/week)

Week 1 — Foundations & Subnetting

• Day 1–2: Study addressing basics; do 2 subnetting tests (timed).
• Day 3–4: VLSM & IPv6 practice tests; review mistakes.
• Day 5: Mixed short quiz (10 questions) + flashcards for binaries.

Week 2 — Switching

• Day 1–2: VLANs, trunking tests; practice configs.
• Day 3–4: STP and EtherChannel timed tests.
• Day 5: Troubleshooting lab scenarios and short test.

Week 3 — Routing

• Day 1–2: Static routing & route summarization tests.
• Day 3–4: OSPF/EIGRP conceptual tests and route selection problems.
• Day 5: Lab-style routing troubleshooting test.

Week 4 — Security & Full-length

• Day 1–2: ACLs, device hardening, DHCP snooping tests.
• Day 3: Mixed-topic mini test (40 questions).
• Day 4–5: Full-length CCNA practice exam (100–120 questions), review weak topics.

How to build and grade your practice tests

• Use a question bank tagged by topic and difficulty. Tag each question: (topic, difficulty 1–5, skills tested).
• Grade by correct/incorrect, then log per-topic accuracy and time per question.
• After each test: review every incorrect question, write a 1–2 sentence root-cause note, and add a follow-up practice item.

Tools & resources (short list)

• Packet tracer or GNS3 for labs.
• Timed quiz platforms with per-question review.
• Spaced-repetition flashcards for subnetting and commands.

Quick checklist before exam

• 90%+ on topic tests for Subnetting & Switching; 85%+ on Routing; 90%+ on Security mini-tests.
• Several timed full-length passes with consistent 80%+.
• Comfortable doing subnetting in under 2 minutes per question.

Good luck — focus on topic drills, simulate timing, and actively review errors until those areas hit the target accuracy.