CloudLabBox
Try the free demo

CCNP ENCOR lab 11 of 36

Troubleshoot multi-area OSPF

A change window has gone wrong and four tickets are open against Fernhill's OSPF network. Work through them with a structured method, find five realistic faults, and restore the designed DR.

Run this lab

It needs Lite: its 6 nodes are set to 6 vCPU and 3,584 MB in total. That fits the free demo too.

In your workspace: Shared, then CCNP ENCOR 350-401 guided labs, then 11 - Troubleshoot multi-area OSPF

Try it free for 30 minutesRun it on Lite from £3 a day

The free demo needs no card and no email. Every lab plan includes every guided lab.

Level
Advanced
Time
About 75 minutes
Nodes need
6 vCPU, 3,584 MB
Smallest plan
Lite

The scenario

Last night a contractor "tidied up" Fernhill Freight's OSPF configuration during a change window. This morning the service desk has four tickets:

  1. INC-4411 Bristol staff (PC1) can't reach anything outside the Bristol office.
  2. INC-4412 Nobody can reach the Glasgow staff LAN (10.30.10.0/24).
  3. INC-4413 The HQ server farm (10.10.30.0/24) has disappeared from every routing table.
  4. INC-4414 R3 keeps logging OSPF messages, and the core monitoring shows R3 with no full adjacencies on the CORE segment.

The intended design is the one you built in lab 8, and it's printed on the canvas. Fix every fault without redesigning anything: the change record says nothing should have changed. Close each ticket only when you've proved it's fixed.

DeviceInterfaceAddressAreaNotes
R1Gi0/0 / Gi0/1 / Lo010.0.0.1/24 / 10.0.14.1/30 / 10.255.0.10 / 1 / 0ABR, BDR (priority 100)
R2Gi0/0 / Lo0 / Lo1010.0.0.2/24 / 10.255.0.2 / 10.10.30.1/240DR (priority 255), only Gi0/0 sends hellos
R3Gi0/0 / Gi0/1 / Lo010.0.0.3/24 / 10.0.35.1/30 / 10.255.0.30 / 2 / 0ABR, priority 0
R4Gi0/1 / Gi0/2 / Lo010.0.14.2/30 / 10.20.10.1/24 / 10.255.0.41Gi0/2 passive
R5Gi0/1 / Lo0 / Lo1010.0.35.2/30 / 10.255.0.5 / 10.30.10.1/242–
PC1eth010.20.10.10/24, gateway 10.20.10.1–Bristol staff PC

All WAN links are point-to-point, every router uses a 10000 Mbit/s reference bandwidth, and router IDs are n.n.n.n.

Topology: R1, R2 and R3 share the CORE segment · R1 Gi0/1 — R4 Gi0/1 · R3 Gi0/1 — R5 Gi0/1 · R4 Gi0/2 — PC1.

What you’ll practise

  • Apply a structured troubleshooting method instead of guessing
  • Check the OSPF neighbour requirements one by one: area, timers, MTU, network type, passive interfaces
  • Use show commands, logs and targeted debugs to find why an adjacency or a route is missing
  • Explain why a fixed network can still have the wrong DR, and restore the design

The tasks

  1. Plan your approach
  2. INC-4411: Bristol is cut off
  3. INC-4412: Glasgow is unreachable
  4. INC-4413: the HQ servers are missing
  5. INC-4414: R3 can't finish on the CORE segment
  6. Check the design, not just the symptoms
  7. Prove the tickets are fixed

The Lab Tasks pane has the scenario, these tasks, the checks to run, hints and the full solution.

Topology and devices

The network as it opens in EVE-NG, drawn from the lab’s own canvas, and the image each node runs.

Topology of Troubleshoot multi-area OSPF6 nodes and 1 network, 6 links. Every link is listed as text below the diagram.R1R2R3R4R5PC1COREGi0/2eth0Gi0/0Gi0/1Gi0/1Gi0/1Gi0/1Gi0/0Gi0/0
6 nodes and 1 network, with the interface names each link uses. On a narrow screen, scroll the diagram sideways.
Every link, as text
  • R1 Gi0/0 to CORE (network)
  • R2 Gi0/0 to CORE (network)
  • R3 Gi0/0 to CORE (network)
  • R1 Gi0/1 to R4 Gi0/1
  • R3 Gi0/1 to R5 Gi0/1
  • R4 Gi0/2 to PC1 eth0
Nodes in Troubleshoot multi-area OSPF, with the image each runs and the vCPU and RAM it’s set to
NodeDeviceImage in Add NodeSet to
R1Cisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
R2Cisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
R3Cisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
R4Cisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
R5Cisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
PC1VPCS hostBuilt in to EVE-NGCounted as 1 vCPU, 1,024 MB

How to open this lab

  1. Sign in to your workspace at lab.cloudlabbox.com.

  2. In File Manager, open Shared, then the folder CCNP ENCOR 350-401 guided labs.

  3. Open 11 - Troubleshoot multi-area OSPF and start its nodes, then open Lab Tasks for the scenario and the steps.

The lab is read-only. You can start the nodes and configure the devices, but changes to the topology can’t be saved. To change it, rebuild it in your own folder.

More CCNP ENCOR labs

All CCNP ENCOR labs

Related labs in other courses

CloudLabBox is independent of Cisco. The lab follows exam topics and isn’t vendor training material; vendor names identify the exams and the images in the workspace.