Labs

Hands-on Cisco IOS XE lab walkthroughs. Each lab ships with a real CML topology, configs you can paste, and verified show output. Articles tagged Labs cover the full CCNA 200-301 blueprint across Network Fundamentals, Network Access, IP Connectivity, IP Services, and Security Fundamentals.

Latest

Patch Panel feature image: route redistribution on Cisco IOS XE with real O E2 routing table output

IP Routing · Jul 11, 2026

Route Redistribution on Cisco IOS XE: The Complete Multi-Protocol Guide

Most networks do not run one routing protocol. Mergers bolt an EIGRP shop onto an OSPF backbone, a campus hands

Jaime

Troubleshooting EIGRP missing routes feature image with real filtered routing table output

EIGRP · Jul 11, 2026

Troubleshooting EIGRP Route Advertisement and Missing Routes

The neighbors are up, the interfaces are clean, and yet a route that should be in the table simply is

Jaime

Empty EIGRP neighbor table on R1 next to a repeating DUAL K-value mismatch log message

EIGRP · Jul 11, 2026

Troubleshooting EIGRP Neighbor Adjacencies: The Loud Failure and the Silent One

Two routers, two broken adjacencies, one log message. Real CML captures on IOS XE 17.18.2 show the %DUAL-5-NBRCHANGE K-value mismatch that repeats every few seconds, the AS mismatch that logs absolutely nothing, and what both look like the moment they recover.

Jaime

EIGRP route filtering feature image with real distribute-list and prefix-list output

EIGRP · Jul 11, 2026

EIGRP Route Filtering with Distribute Lists and Route Maps

Advertising every route to every neighbor is the default, not a requirement. Sometimes a spoke should never learn the DMZ

Jaime

Terminal showing an EIGRP route in Active state with reply pending and SIA status flags

EIGRP · Jul 11, 2026

EIGRP Query Process and Stuck-in-Active (SIA) Explained with Real Captures

A route in Active state with a reply outstanding, captured live on IOS XE 17.18.2 in CML: the r and rs status flags that name the silent neighbor, why packet loss gives you neighbor flaps instead of SIA, and why modern IOS XE usually logs retry limit exceeded before it ever prints %DUAL-3-SIA.

Jaime

EIGRP authentication feature image showing a real MD5 authentication mismatch and Auth failure log

EIGRP · Jul 11, 2026

EIGRP Authentication: MD5 and SHA in Classic and Named Mode

An unauthenticated EIGRP interface will happily form an adjacency with anything that speaks the protocol. That means anyone who can

Jaime

EIGRP variance unequal-cost load balancing feature image with real traffic share count output

EIGRP · Jul 11, 2026

EIGRP Unequal-Cost Load Balancing: Variance Explained

Every routing protocol can load balance across equal-cost paths. EIGRP is the only IGP on Cisco routers that can

Jaime

EIGRP route summarization feature image with real IOS XE Null0 summary route output from a CML lab

EIGRP · Jul 11, 2026

EIGRP Route Summarization and Default Routes

Route summarization is one of those EIGRP features that looks like a simple address-shortening trick but quietly solves three

Jaime

Installing CML 2.10 Docker container images

Cisco Modeling Labs · Jun 28, 2026

How to Install the Missing Docker Container Images in Cisco Modeling Labs 2.10

CML 2.10 shows the Docker node definitions but no image definitions. Here is how to install the container images (net-tools, nginx, Snort, TACACS+, Splunk and more) from Cockpit.