CCNA Foundations: OSPF Day 6 — Route Summarization at the ABR
A compact, enterprise-clean, 5-node CML lab that builds on OSPF multi-area design. You will enable OSPF across a small core–ABR–branch topology, advertise multiple branch networks in area 10, and summarize them at the ABR using 'area range'. You will verify that specific inter-area routes are replaced by a single summary in area 0 while preserving end-to-end reachability between hosts.
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EIGRP Manual Route Summarization (AS 100)
Implement classic EIGRP manual summarization on R1 to collapse four contiguous /24 loopback routes into a single /22 summary toward R2, reducing R2’s routing table entries while preserving reachability.
OSPFv2 Multi-Area with ABR Summarization (Redundant Core)
Deploy a 5-node OSPFv2 lab featuring a redundant area 0 triangle (R1–R2–R3) and an ABR (R3) connecting to area 1 with branch networks on R4. A client on R1’s area 0 LAN validates reachability to branch loopback networks summarized by the ABR. You will set explicit router-ids from Loopback0, use passive-interface default, advertise R4’s loopbacks as /24s using ip ospf network point-to-point, and summarize area 1 into a /23 on the ABR. Verify FULL adjacencies, a single O IA summary on R1, and end-to-end connectivity. Troubleshoot an introduced area mismatch and interface/addressing issues.
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.
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.