CCNA troubleshooting labs — Page 3

CCNA Capstone: Port Security Troubleshooting

Advanced CCNA port-security troubleshooting on a pure Layer-2 design. Two access switches linked by an 802.1Q trunk carry a Users VLAN across closets. Three Alpine Linux hosts are pre-addressed. The lab is intentionally shipped with multiple classic faults: one access port is err-disabled due to a prior port-security shutdown, one user-facing port lacks port-security altogether, another has the wrong violation mode and an overly restrictive maximum, and one port has an incorrect static secure-MAC configured. Your job is to diagnose using show commands, restore connectivity, and implement the intended security posture with sticky MACs, the correct maximum, the proper violation mode, and errdisable auto-recovery—without placing port-security on the trunk.

CCNA55 min6 objectives

CCNA Static Routing: Redundant Branch Triangle

Build a 3-router triangle with two branch LANs and real Alpine clients. Deploy primary static routes via the hub and floating backup statics over a direct branch-to-branch link. Verify reachability, path selection, and failover by simulating a hub outage.

CCNA65 min5 objectives

CCNA Port-Sec 9: Multi-Port Sticky Restrict Policy

Advanced CCNA switchport port-security rollout on multiple access ports across two Layer-2 switches with a trunk. You will standardize a consistent edge policy (sticky MAC learning, maximum 1, violation restrict) on all host-facing access ports while leaving the uplink trunk exempt from port-security. Includes a realistic drift on the trunk allow-list and VLAN database to fix before validating end-to-end user VLAN transport. Pure Layer-2: no SVIs or routing.

CCNA58 min6 objectives

Static Routing Between Branches Through an HQ Hop

Deploy IP addressing and bidirectional static routing across a three-router topology to connect two branch LANs through an HQ hop. Practice verification from end hosts, analyze routing tables, and troubleshoot asymmetric reachability.

CCNA45 min5 objectives

IPv4 Addressing Fundamentals: Interfaces, Gateways & Reachability

Beginner CCNA lab focusing on IPv4 addressing and basic Layer 3 verification on a small branch network. You will assign IP addresses to router interfaces, confirm end-host default gateways, and verify connected reachability using host-based pings. You will also learn to read 'show ip interface brief' and 'show ip route' to confirm operational state before any routing beyond directly-connected networks is configured.

CCNA50 min5 objectives

Troubleshoot a Branch ROAS: VLANs, Trunks & Port Security

Deploy and troubleshoot VLANs, 802.1Q trunks, and port security in a realistic small-branch ROAS design. You will stand up VLANs 10/20/99 with a hardened trunk native VLAN 999, configure sticky port security on access ports, correct a misassigned VLAN, and resolve an err-disabled port caused by a port security violation. Finish by verifying end-to-end host connectivity across VLANs.

CCNA55 min5 objectives

Standard ACL: Permit Host & Subnet, Deny Others

Beginner CCNA ACL lab on a compact 5-node CML-Free topology. You will configure static routing end-to-end, implement source NAT (PAT) at the source edge, and then build a standard numbered ACL near the destination to allow a single NATed host and a specific subnet while denying all others. You will validate with pings from end hosts, observe ACL hit counters and NAT translations, and troubleshoot common mistakes such as ACL placement, wildcard masks, and pre-/post-NAT address matching.

CCNA55 min7 objectives

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CCNA: Named ACLs & Editing by Sequence Number

Hands-on ACL practice using named standard and extended ACLs, applied with correct placement and direction, edited by sequence number, and verified with counters and end-host tests. The lab adds a realistic NAT edge to expose order-of-operations pitfalls without obscuring data-plane ACL effects.

CCNA75 min6 objectives

ACL Wildcard Masks: Match Host, Subnet, and Range

Hands-on CCNA ACL practice using standard ACLs and wildcard masks to allow a single host, a contiguous range, and an entire subnet while proving a deny. You will place the ACL near the destination, order statements correctly, verify with end-host pings and ACL counters, and troubleshoot common mistakes.

CCNA55 min5 objectives

ACL Segmentation Policy on Multi-LAN Router

Deploy and verify multiple IPv4 ACLs on a single router that terminates three distinct LANs (Client, Server, and Management). You will place an extended ACL inbound on the Client interface to allow only specific services to the Server and block access to Management, a standard ACL outbound on the Management interface to enforce destination-side protection by source, and a VTY access-class to restrict router SSH to the Management subnet only. Validate with end-host tests that permitted flows succeed while denied flows are provably blocked, and use ACL hit counts and logs to troubleshoot.

CCNA70 min5 objectives

Multi-VLAN Segmentation: 3 VLANs & Trunk Alignment

Hands-on CCNA campus switching lab with two Layer-2 switches and three VLANs (Users 10, Servers 20, Management 99) extended over a single 802.1Q trunk. Learners deploy VLANs and access ports, harden the trunk (native VLAN 999, explicit allow-list, nonegotiate), and validate isolation. The lab ships with a trunk-carried outage: VLAN 10 traffic reaches its gateway successfully, but VLAN 20 traffic does not. You will diagnose from end hosts, confirm switch states, and correct the trunk so that same-VLAN traffic to the gateway SVI succeeds while inter-VLAN forwarding remains absent.

CCNA75 min5 objectives

CCNA: VLAN DB & Trunk Allow-List Drift Recovery

Hands-on CCNA VLAN lab: build VLANs with names, assign access ports, harden and verify 802.1Q trunks, and troubleshoot a broken allow-list that prevents a VLAN from traversing the SW1–SW2 trunk. Includes router-on-a-stick gateways, management VLAN, and end-host validation.

CCNA65 min7 objectives

VLAN Troubleshooting Capstone: Native Mismatch & VLAN Drift

Advanced CCNA L2 troubleshooting in a compact branch. Some PCs can't reach their default gateway or other departments across two switches and a router-on-a-stick gateway, and your monitoring system has flagged a switching/trunking problem on the path. Validation is performed from the endpoints (Alpine hosts) using pings and ARP, and trunks are hardened with a non-default native VLAN.

CCNA65 min6 objectives

Native VLAN & Trunk Mismatch: Detection and Recovery

Configure VLANs and 802.1Q trunks across two access switches with a router-on-a-stick gateway. Intentionally misconfigure the native VLAN and trunk allow-list to observe loss of intra-VLAN connectivity, detect the mismatch using switch warnings and show commands, and then remediate to restore user reachability. Validates VLAN segmentation, trunking symmetry, and troubleshooting skills for CCNA candidates.

CCNA65 min5 objectives

CCNA Static Routing: Bidirectional End-to-End Connectivity

Hands-on CCNA static routing lab: build a small hub-and-spoke with two stub routers and a hub router. Configure default routes on the spokes and specific static routes on the hub so two user LANs reach each other end-to-end. Validate from real hosts and practice first-hop and return-path troubleshooting.

CCNA45 min5 objectives

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CCNA Static Routes: Manual Summarization

Hands-on CCNA static routing and manual summarization lab using a compact HQ–Branch–Remote topology. You will replace three specific static routes to Branch networks with a single /22 summary at HQ, verify end-to-end host reachability, observe the routing table reduction, and prevent over-aggregation loops by adding a Null0 discard route at Branch. A recommended step has you add the same /22 summary at Remote (replacing its default) to practice summarization on both sides.

CCNA55 min6 objectives

CCNA Static Routing: Troubleshooting Broken Static Routes

Hands-on CCNA static routing troubleshooting in a realistic three-router core/edge topology with two user LANs. Static routing on the network was recently changed and users at SITE-A (10.10.10.10) and SITE-B (10.30.30.10) can no longer reach each other; you will investigate the routers' route tables and next-hop reachability to diagnose and restore full bidirectional connectivity.

CCNA55 min5 objectives

OSPF Cost & Path Selection: Deterministic Control (3 Routers)

Build a 3-router triangle with two end-to-end paths between Branch A and the Data Center. Stand up OSPF area 0, create an ECMP condition, then intentionally steer traffic using ip ospf cost. Verify from the end hosts and troubleshoot common OSPF control-plane mismatches.

CCNA55 min5 objectives

OSPF Multi-Area: ABR Area Mismatch and Route Repair

Build and troubleshoot a compact multi-area OSPF design with a single ABR between area 0 and area 10. You will deploy OSPF, observe an adjacency failure caused by an area mismatch on one transit link, repair it, and validate that routes propagate end to end between two user LANs.

CCNA & CCNP55 min4 objectives

OSPF MD5 Authentication: Backbone Integrity and Area Mismatch

Deploy OSPFv2 with MD5 authentication on backbone links, deliberately trigger and diagnose an area mismatch adjacency failure, then fix it and restore end-to-end reachability between two branch hosts in a compact three-router topology.

CCNA & CCNP68 min5 objectives

Layer 2 Access Hardening: PortFast, BPDU Guard & Sticky MAC

Hands-on CCNA Layer 2 switching lab: build VLANs, access ports, hardened 802.1Q trunks, and basic port-security across two access switches and an L2 core. Verify segmentation end-to-end from real hosts and practice troubleshooting native-VLAN and port/VLAN mismatches.

CCNA55 min5 objectives

OSPFv2: Router IDs, Neighbor States, and Loopback Adjacency

Deploy OSPFv2 across three routers with unique, loopback-derived router-ids. Observe OSPF neighbor state transitions, advertise loopbacks and LANs, and troubleshoot an adjacency failure caused by a duplicate router-id. Validate full end-to-end reachability from client hosts after fixing the issue.

CCNA55 min5 objectives

CCNA: OSPF Passive Interfaces & Default Origination

Deploy OSPFv2 across a 3-router, 2-LAN branch/core/edge topology. Mark LAN-facing interfaces as passive so they do not send OSPF hellos or form adjacencies. Originate a default route only from the edge router and verify default propagation end-to-end using real client traffic. Includes realistic troubleshooting around missing adjacencies, non-propagating defaults, and unreachable external destinations.

CCNA70 min5 objectives

OSPFv2 Single-Area Fundamentals: Adjacency and Area 0 Basics

Hands-on CCNA beginner lab: build a 3-router chain with end hosts, enable OSPFv2 area 0, form full adjacencies, advertise loopbacks and LANs, verify route propagation end-to-end, and intentionally create then resolve an OSPF area mismatch on a transit segment.

CCNA55 min5 objectives

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