JNCDS-DC study plan

Diagram a three-tier and a spine-leaf data center topology from memory, labeling every layer and its failure domains

Explain underlay versus overlay separation and where each lives in a VXLAN EVPN fabric

Compare oversubscription ratios for compute, storage, and management traffic and justify a chosen ratio for a given workload

List the physical cabling and optics standards you would specify for 10G/25G/100G server and fabric links

Identify single points of failure in a sample design and propose redundancy fixes

Configure and verify VLANs, trunks, and 802.1Q tagging on a simulated pair of switches

Build a working LACP port-channel and demonstrate behavior when one member link fails

Configure RSTP/MST and explain how it interacts with vPC or MC-LAG topologies

Contrast vPC, MC-LAG, and stack-based designs on control-plane independence and upgrade impact

Trace a frame end-to-end through a leaf-spine fabric and describe every encapsulation and lookup stage

Deploy a VXLAN EVPN fabric with an IGP underlay and BGP EVPN control plane in a virtual lab

Explain the roles of VTEP, VNI, route type 2, route type 3, and route type 5 in forwarding and MAC/IP learning

Configure anycast gateway and symmetric IRB, then verify inter-VNI routing

Describe multi-homing options such as EVPN multihoming and when each is appropriate

Troubleshoot a simulated failure where a VNI fails to come up and document the isolation steps

Design an IP fabric underlay using eBGP with unique ASNs and verify ECMP hashing across all spine links

Compare OSPF, IS-IS, and eBGP as underlay protocols on convergence, scale, and operational simplicity

Explain BGP best-path selection order and apply it to a multi-homed data center edge scenario

Configure BFD and tune failure detection for fabric links

Document an addressing plan with loopbacks, point-to-point /31s, and summarization boundaries

Design a data center edge that connects to multiple ISPs and explain route filtering, local preference, and AS-path prepending choices

Compare stretched Layer 2 versus Layer 3 to the edge and state the tradeoffs for workload mobility

Plan a migration from a legacy three-tier network to a spine-leaf fabric with minimal downtime

Describe overlay-to-external routing using EVPN route type 5 and verify it in the lab

Evaluate VRF-lite and MPLS-free segmentation options for tenant isolation

Design a segmentation model using VRFs and security zones mapped to application tiers

Configure ACLs and a stateful firewall insertion point, then verify permitted and denied flows

Explain micro-segmentation approaches in a virtualized data center and how policy follows the workload

Plan network services including DHCP relay, NTP, DNS, and first-hop redundancy for a fabric

Describe how to secure the control plane with authentication, role-based access, and management-plane filtering

Use a Python script with a network library to pull interface state from multiple devices and export structured data

Write an idempotent configuration template and apply it to at least three devices in the lab

Compare agent-based, agentless, and API-driven automation models and pick one for a given environment

Set up a source-of-truth data model for device inventory, VLANs, and underlay links

Describe CI-style validation such as config diffing and pre-change compliance checks

Complete a timed full-length practice set and score each domain separately to find weak areas

Re-derive the top failure modes and design tradeoffs for each domain without notes

Re-run the two weakest labs from earlier weeks until they pass cleanly

Build a one-page cheat sheet of numbers, protocol roles, and design rules you keep missing

Review every missed practice question and write the underlying concept in your own words