CCIE-level material for engineers past the CCNP line. Articles tagged CCIE cover expert-track routing, overlays, security and automation, with full configs and real device output from CML.
On-box Python puts automation scripts on the IOS XE device itself, so they run even when the management network is down. Covers the cli module, where scripts run, and the honest platform picture, with a fully captured off-box pipeline as reference.
Guest Shell is a Linux container running on your router's own hardware, with access to the IOS XE CLI from inside it. Run Python and script the box with no external automation host. What it is, why it matters, and where you can run it.
NAT, DHCP, and IP SLA faults rarely leave clues in show ip route. Five services ticket scenarios with the exact translation table, binding, or tracking object to check for each, grounded in real lab behavior.
DHCPv6 prefix delegation, general prefixes, and NPTv6: the IPv6 services engineers often skip, shown with real CML output of a delegated prefix flowing all the way to a downstream interface.
Embedded Packet Capture puts Wireshark-grade capture inside the IOS XE router itself: no SPAN, no capture laptop, no cabling. Includes a real on-router capture from a CML lab and the syntax difference that will bite you.
Build SNMPv3 in production form: users, groups, views, and the three security levels. The payoff is a real encrypted trap arriving and being decrypted on a Linux receiver, with no cleartext community strings on the wire.
The IOS DHCP server does far more than network, default-router, dns-server. This article covers options for PXE boot and phones, DHCP classes, and manual bindings, with real lease output from a CML lab.
Two customers with identical 10.5.5.0/24 subnets reach one shared exit through a single router. VRF-aware NAT on IOS XE keeps them separate, and this CML lab build shows two translation tables holding identical inside-local addresses.
One MPLS circuit, two WAN Edge routers: without TLOC extension your redundancy is fiction. This post explains how one router uses a transport physically connected to the other and how it fits a redundant branch design.
DIA lets branch internet traffic exit locally instead of backhauling to a data center firewall. See how it works in Catalyst SD-WAN, how the data policy is configured, and the security question local breakout forces you to answer.
Localized policy is what runs on the SD-WAN edge itself: interface ACLs, QoS treatment, and route policies filtering what a branch redistributes into OMP. Syntax follows Cisco's current 20.x documentation.
Application-aware routing measures loss, latency, and jitter on every transport and steers each app onto a path that meets its SLA. This article covers centralized data policy, SLA classes, and how the fabric measures paths, per Cisco's 20.x docs.