Cisco CML lab archive — every past daily CCNA & CCNP lab

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.

CCNA Static Routing: Floating Static Route as Backup Path

Deploy primary static routes between two branch LANs via a hub router and add a higher-AD floating static for a direct inter-branch backup. Verify end-to-end reachability, simulate a hub outage to trigger automatic failover, then restore the primary path. Includes realistic addressing, unique /30 transits, and host-based verification.

CCNA IPv6 Static & Default Routing End-to-End Practice

Hands-on IPv6 static and default routing across a 3-router, 2-LAN topology with end-user hosts. You will enable IPv6 unicast routing, apply IPv6 addressing, configure hub-and-spoke static and default routes, and validate bidirectional host reachability. The guide provides scenario context, step-by-step tasks with the why behind each action, and targeted troubleshooting.

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.

CCNA Static Routing: Host vs Subnet (/32 vs /24)

Deploy a compact two-site topology with a WAN core and two end hosts to practice IPv4 static host routes (/32) versus subnet routes (/24). You will configure a specific /32 host route to steer one destination host over the direct R1–R3 path while a broader /24 for the same remote LAN is sent via the R1–R2–R3 core. Validate with show commands and traceroute, then troubleshoot longest-prefix match and return-path issues.

CCNA Static Routing: 3-Router Full-Mesh

Design and implement a 3-router full-mesh with two edge LANs using static IPv4 routes only. Edges use primary defaults toward the core plus floating (higher AD) backup defaults; the core uses specific routes for the edge LANs. Validate bidirectional reachability, path choice, and failover behaviors from real hosts.

CCNA Foundations Series: Layer 2 Day 5

Implement VLANs, 802.1Q trunking, router-on-a-stick inter-VLAN routing, and access-layer port security on a compact branch network with two access switches and two endpoints. You will configure segmentation (VLANs 10, 20, 99), hardened trunks with a dedicated native VLAN 999, Layer 3 gateways on a core router, and sticky MAC port security on user-facing ports. Verify end-to-end reachability and remediate common misconfigurations like missing allowed VLANs, native VLAN mismatches, and unauthorized endpoint moves.

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OSPF Stub vs Totally-Stubby: Fault & Recovery

Deploy a compact enterprise multi-area OSPF with a backbone (area 0) and one branch area (area 10). You will configure area 10 as a stub, then transition it to a totally-stubby area from the ABR, validate reduced LSDB and routing tables, and simulate an operational fault (area mismatch) to diagnose adjacency loss and restore full transit. The lab uses three routers and two hosts to verify end-to-end reachability and real-world outcomes.

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.

OSPF Inter-Area Summarization with ABR Area Range

Build a 5-node CML lab to design OSPFv2 across two areas with an ABR that summarizes non-backbone routes using area range. Validate adjacencies, end-to-end reachability, and that the backbone learns a single summary in place of specific inter-area routes. Intentionally introduce an area mismatch, diagnose why the adjacency does not form, and repair it.