Catalyst Center exposes everything through a REST API: inventory, intent, and assurance data at scale. This article explains the API model and the categories of endpoint, with documentation-style request and response examples.
A script that ignores HTTP response codes eventually lies about success. This covers the codes that matter for RESTCONF, Catalyst Center, and SD-WAN Manager APIs, what 200, 404, and 500 tell you, and how to act on each.
YANG is the schema language behind NETCONF, RESTCONF, and gNMI. This post explains data models for network engineers: what a model defines, the difference between native and OpenConfig models, and how to actually explore one.
RESTCONF exposes the same YANG models as NETCONF over ordinary HTTPS: GET to read, PATCH to modify, PUT to replace, DELETE to remove. If you can use curl or Python requests, you can drive a Catalyst 8000v with it.
NETCONF replaces screen-scraping with structured XML over SSH against YANG models. This walkthrough drives Cisco IOS XE with ncclient from a real Linux automation host, from first hello to config change.
EEM runs on the router itself, watching for events and acting on them with no external server to depend on. This article builds three EEM applets on Cisco IOS XE for config automation, troubleshooting, and data collection, and fires all three for real.
VRFs, VLANs, VXLAN, and LISP all segment a network at different layers. This decision framework shows what each one actually separates and when to use it, so you do not reach for a fabric when a VLAN would do.
The network no longer stops at the physical switch port. Hypervisors, virtual switches, and VM networking explained for engineers who know networking but not the compute side, where your VLANs actually terminate.
The hard engineering in SD-Access adoption is the border where the fabric meets your existing campus. This covers how VXLAN and LISP traffic crosses that boundary and the realistic migration paths that keep users up.
SD-Access is LISP as the control plane, VXLAN as the data plane, and Catalyst Center operating the whole thing. This article explains the fabric architecture, its roles, and the policy model, extending the network virtualization cluster.
VXLAN without a control plane is flood-and-learn, and that does not scale to a real data center. BGP EVPN is what fabrics actually use: what it advertises, the route types that carry reachability, and why it replaced flooding everywhere.
VXLAN stretches Layer 2 across a routed network by wrapping Ethernet frames in UDP. This deep dive takes the encapsulation apart to the byte level with a real crafted-and-decoded packet, covering VNIs and VTEPs.