How to pass the CCNA in 90 days

Most CCNA study plans assume you never miss a day. This one assumes you will, and tells you what to drop first.

Ninety days is enough for the CCNA 200-301 if you are disciplined about order. Most people fail not because they ran out of time but because they spent six weeks on OSPF theory and walked into the exam unable to subnet at speed.

Phase 1 — Days 1 to 20: fundamentals and subnetting

Everything else in the exam sits on top of addressing. If you cannot look at 10.20.30.0/26 and say the range, broadcast and usable hosts in under fifteen seconds, stop and fix that before touching a routing protocol.

• The OSI and TCP/IP models — one evening, no more. You need the vocabulary, not a religion.
• Cabling, interfaces, duplex and speed. Boring, and it appears on the exam.
• IPv4 addressing, masks and subnetting to fluency. This is the phase.
• IPv6 addressing, abbreviation rules, and the address types.

Practise subnetting daily, ten questions, timed. It is the only topic where speed matters more than depth, because it appears inside other questions you are being timed on. Our method for subnetting under pressure covers the approach we recommend.

Phase 2 — Days 21 to 45: switching

Now get your hands on a console. Reading about VLANs teaches you nothing about what happens when a trunk has the wrong native VLAN.

• MAC learning and the forwarding table — watch it populate, do not just read about it.
• VLANs, access ports, trunks, and the native VLAN mismatch that will bite you.
• Spanning tree: root election and port roles. Enough to reason about it, not to implement it from memory.
• EtherChannel, basic port security.

Rule for this phase: every concept gets configured at least once. If you only ever read about a switchport trunk allowed vlan mismatch, you will not recognise it as the fault in a troubleshooting question.

Phase 3 — Days 46 to 70: routing

• How a routing table is actually consulted: longest prefix match first, then administrative distance.
• Static routes, default routes, and floating static routes for backup paths.
• OSPF single-area: neighbours, cost, and reading show ip route with confidence.
• Inter-VLAN routing, both router-on-a-stick and SVIs.
• NAT and PAT, DHCP, and the services that break in ways that look like routing problems.

Phase 4 — Days 71 to 85: security, automation, wireless

These are worth real marks and are usually under-studied because they come last in every course. ACLs in particular are heavily tested and easy to get wrong by one line.

• Standard and extended ACLs — including the order of operations and the implicit deny.
• Device hardening, AAA concepts, port security.
• WLAN fundamentals and WLC configuration at a conceptual level.
• Automation, REST APIs, JSON, and the controller-based networking vocabulary.

Phase 5 — Days 86 to 90: rehearsal only

No new material. Full-length timed exams, review every miss, and re-lab the topics you got wrong. If a practice score is above 85% consistently and you can subnet at speed, sit it.

What to cut when you fall behind

You will fall behind. Cut in this order:

Note what is on the right: it is almost entirely things you can only get by configuring, not by watching. When time is short, people cut labs first because labs feel slow. That is exactly backwards — labs are where the retention is.

A weekly rhythm that survives real life

• Every day: ten subnetting questions, timed. Fifteen minutes.
• Three evenings: new material, then immediately lab it.
• One evening: revisit everything you got wrong that week.
• Weekend: one longer lab that combines several topics.

The "revisit what you got wrong" session is the one people skip, and it is worth more than the two new-material evenings combined. Your wrong answers are a personalised syllabus that nobody had to write for you.