EIGRP is the only Cisco IGP that load balances across unequal-cost paths. This lab walks variance on live IOS XE: the topology table, the feasibility check, variance 2 in named mode, and the traffic share counters that prove the split.
EIGRP summarization shrinks topology tables, speeds convergence, and bounds queries. Configure it in classic and named mode on IOS XE, watch the Null0 discard route appear, and advertise a default route with summary-address 0.0.0.0/0.
TFTP and FTP behave very differently when you copy configs and images off a router. This article backs up a real IOS XE config over both to a Linux server, with genuine transfer output and an honest speed comparison.
DHCP discovery is broadcast and routers do not forward broadcasts, yet central DHCP servers work fine. This article builds server, relay, and client on three IOS XE routers and shows how ip helper-address makes relay work, reading state on all three.
Configure Cisco IOS XE logging to a real Linux syslog server: severity levels, logging host, synced clocks, and how to read the actual messages that arrive at the collector.
SNMP architecture explained, then put to work: polling a real Cisco IOS XE router from Linux with both SNMPv2c and SNMPv3, including what wrong credentials look like. Covers managers, agents, OIDs, and MIBs.
Wrong device time breaks certificate validation, log correlation, and time-based auth. This article deploys NTP on real Cisco IOS XE: one router as ntp master, the others syncing to it, with genuine show output at every stage.
Static NAT, dynamic NAT, and PAT configured on a real IOS XE router in CML, with the translation table read after each one. R1 is the NAT boundary and you see exactly how each flavor rewrites addresses.
CCNA v1.1 added AI and machine learning to the blueprint. This post covers the learning types, the predictive versus generative split, real network operations use cases, and the honest limits, framed for the exam and the job.
Ansible, Puppet, Chef, and Terraform compared on the axes that separate them, then Ansible runs for real against three live Cisco IOS XE routers, including the idempotency gotcha that bites everyone the first time.
REST is how your scripts talk to a network controller. This guide covers HTTP verbs, status codes, authentication, and JSON structure, grounded in real requests against a live Cisco Modeling Labs controller.
Control plane vs data plane, northbound and southbound APIs, and the overlay, underlay, and fabric vocabulary, mapped to the Cisco products you will meet. CCNA domain 6 concepts with the routing and switching you already know kept at the center.