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BeginnerPublished 2026-06-25

VLAN Fundamentals: Creating & Assigning Access Ports

Free preview — the first lab of VLANs & Network Segmentation

Hands-on CCNA lab to practice creating VLANs on a single Layer-2 switch and assigning access ports. You will segment a flat network into two VLANs, place hosts into the right VLAN, and verify that intra-VLAN pings succeed while inter-VLAN pings fail (no routing present). Includes realistic verification and troubleshooting.

Track
Est. time
45 minutes
Difficulty
Beginner
Topics

Learning objectives

  • Create VLANs on a Cisco Layer-2 switch and verify the VLAN database.
  • Assign switch access ports to specific VLANs for host segmentation.
  • Validate hosts in the same VLAN/subnet can communicate (ping).
  • Validate that hosts in different VLANs/subnets are isolated at Layer-2 (no routing).
  • Troubleshoot VLAN membership and port assignment using show commands and host-side tests.

Troubleshooting focus

  • The ping from CLIENT10A to CLIENT10B (10.10.10.11) fails, or the Guest pair cannot reach each other: On SW-BR-ACC1, confirm the VLAN exists in show vlan brief and the port is access in that VLAN. No host port should still be in VLAN 1.; Check the host IP and mask. A wrong mask or subnet breaks ARP and the ping.
  • CLIENT10A can ping 10.20.20.10 when it should not: make sure no SVI for VLAN 10 or 20 has routing enabled and no external router is connected. This lab is pure Layer 2.
  • One host is isolated while its VLAN partner works: verify cable-to-port mapping matches your port configuration — a swapped cable strands a host in the wrong VLAN. Confirm the interface is up and not err-disabled by BPDU Guard.
  • The first pings time out then recover: PortFast is missing on that host port, so STP transitions delay bring-up. Enable it on true edge ports only.

Topology

Lab topology diagram

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Study this topic

Free guides, a command cheat sheet, and graded practice for this lab's topic.

Learn VLANs, Trunking & Inter-VLAN RoutingWhat Is a VLAN? VLANs Explained for Beginners

Grade your work

How this lab is graded
  • Build it your way. Where a lab lets you choose a value — a VLAN name, an interface description — grading checks that you configured it, not which name you picked. Names that another line has to reference, like an ACL applied with access-class, are stated in the guide and do have to match.
  • Addresses, modes and protocol keywords are exact. An IP address, a subnet mask, switchport mode trunk, an encapsulation — these carry the meaning of the lab, so they are graded as written in the guide.
  • Grading reads your saved configuration. Export the lab from CML after you have configured it, and make sure anything you set is in the running-config — a change that only exists in a terminal session never reaches the grader.
  • You can submit as many times as you like. Your best score stands, and each attempt tells you which checks passed so you can work the gaps.
  • Scored something you believe is correct? Use Report an issue on this page — that is exactly how the grading fixes in the changelog got found.

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