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

EIGRP Wildcard Masks: Enabling the Right Interfaces

Build a two-router, two-LAN EIGRP domain and practice precise wildcard-masked network statements so only the intended interfaces participate. R1 has an extra LAN on Ethernet0/2 (172.16.99.0/24) that must be excluded from EIGRP. Validate with show commands and end-host pings that the correct LANs are exchanged and the excluded LAN is not advertised.

EIGRP Stub Routing on a Spoke (Hub-and-Spoke, AS 100)

Configure a classic hub-and-spoke EIGRP domain where the single-homed branch (R2) is made an EIGRP stub, limiting query scope while still advertising its LAN. Validate that R1 flags R2 as a stub neighbor, routes still exchange, and query behavior is scoped appropriately.

EIGRP Metric: Steering Paths by Tuning Delay

Tune EIGRP path selection by manipulating cumulative delay. Three routers (R1-R2-R3) form EIGRP 100 adjacencies over three /30 point-to-point links. R3 originates 192.168.30.0/24 on Loopback0. You will enable EIGRP and then increase delay on R1’s direct link to R3 so R1 prefers the indirect path via R2 to reach 192.168.30.0/24. Two Alpine hosts validate end-to-end reachability and path choice.

EIGRP Lab 7: Securing Adjacencies with MD5

Harden EIGRP adjacencies with MD5 authentication between two iol-xe routers over a /30 transit, then validate that only trusted peers form neighbors. You will configure a key chain, bind it to the transit interface, and enable EIGRP (AS 100) to exchange two user LANs. Verification includes neighbor state, key chain presence, and end-to-end host reachability.

CCNA EIGRP: Passive Interfaces

Build and verify EIGRP on a small routed topology while marking the user-facing LAN interface as passive. You will advertise the LAN into EIGRP without forming an adjacency on that segment, preventing rogue neighbors and reducing control-plane noise. Focus on deterministic EIGRP configuration, wildcard-based network inclusion, and verification using show commands.

CCNA Foundations Day 6: Layer 3 Routing Troubleshooting

Troubleshoot classic static routing and connectivity issues in a 3-router, 2-site network. Faults seeded include a missing return route, wrong next-hop/mask, and a missing/misconfigured default route. Learners must identify and correct Layer 3 faults to restore end-to-end reachability between branch clients.

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CCNA HSRP 2: Controlling the Active Router with Priority

Set HSRP priority to deterministically choose the active default gateway on a shared LAN. Two IOS routers (R1, R2) and one access switch serve a small user LAN with a single virtual gateway IP. By default R2 becomes active due to its higher interface IP; raise R1’s HSRP priority so it becomes the designated active router for group 1 while hosts keep a single virtual gateway.

HSRP Preempt: Reclaiming the Active Role

Intermediate CCNA lab focused on HSRP preempt behavior. Two routers share a virtual default gateway on a single user VLAN. The baseline already has HSRP group 1 with R1 at higher priority, but HSRP doesn't preempt by default — if R1 reboots, R2 stays active even after R1 returns. The learner enables preempt on R1 so it deterministically reclaims the active role whenever it's up, keeping the intended primary in control. Verification uses show standby on routers and basic host pings to the virtual gateway.

Tuning HSRP Timers for Faster Failover

Configure HSRP on two routers with a shared virtual gateway and speed up failover by tightening hello/hold timers to 1/3 seconds. Validate deterministic active/standby selection and confirm timer settings via show commands.

HSRP Fundamentals: A Virtual Default Gateway

Build a fault-tolerant default gateway on a single LAN using HSRP. Two routers share one virtual IP so a host keeps the same default route even if one router fails. You will configure basic HSRP group 1 with a shared VIP, verify active/standby roles, and confirm the host can ping the virtual gateway.