zNetLaB › Guided labs › Enterprise
Named EIGRP — and a second path that is worse on purpose
Enterprise Advanced 4 devices 5 checked tasks 100 points Plan lab
Configure EIGRP the way the current syllabus writes it — a name, an address family, an af-interface — then use variance to install a SECOND path to the same prefix, one that is slower than the best. No other protocol here will do that. You build it in a browser, type real commands at each device, and every task below is
checked against the running configuration — so you find out it is wrong before anybody else does.
Open this lab in the simulator
The simulator runs in your browser with nothing to install. This lab is part of the full simulator: open it free for 7 days with a new account, then with a plan. It needs an account, which keeps your progress.
The scenario
Configure EIGRP the way the current syllabus writes it — a name, an address family, an af-interface — then use variance to install a SECOND path to the same prefix, one that is slower than the best. No other protocol here will do that.
Your role: a network engineer on the enterprise team. Level: Advanced Done when: all 5 goals show as passed (100 points).
Network status
Devices: 4 routers, cabled as drawn. No Layer 1 or Layer 2 faults: every link is connected and up. R1 starts with addresses (G0/1 10.0.12.1/30, G0/2 10.0.13.1/30). R2 starts with addresses (G0/1 10.0.12.2/30, G0/2 10.0.24.1/30) and EIGRP 100 already configured. R3 starts with addresses (G0/1 10.0.13.2/30, G0/2 10.0.34.1/30) and EIGRP 100 already configured. R4 starts with addresses (L0 4.4.4.4/24, G0/1 10.0.24.2/30, G0/2 10.0.34.2/30) and EIGRP 100 already configured. Known problems
The network worked and now does not: the scenario above says what users report. The cause is a configuration fault, not a cable. Find it with show commands (interfaces, routes, neighbours, running-config) before you change anything; fix only what is wrong. Goals
R1 runs EIGRP in NAMED mode, as the process CORE (25 pts) …in autonomous system 100, so it peers with the others (20 pts) R1 learns R4’s loopback (15 pts) Variance is set to at least 2 under topology base (20 pts) …and TWO paths are installed for that one prefix (20 pts) The activity, in order
R1 runs EIGRP in NAMED mode, as the process CORE Why: Each goal is a state the lab can check on the running device. Verify with: show running-config …in autonomous system 100, so it peers with the others Why: EIGRP shares routes only with neighbours; a mismatched AS number simply never forms one. Verify with: show ip eigrp neighbors R1 learns R4’s loopback Why: If the prefix is not in the routing table, the router drops packets for it, whatever else is configured. Verify with: show ip route Variance is set to at least 2 under topology base Why: Each goal is a state the lab can check on the running device. Verify with: show running-config …and TWO paths are installed for that one prefix Why: Each goal is a state the lab can check on the running device. Verify with: show running-config Tips
Work in the order given: later goals depend on the earlier ones. After every change, run the verify command before moving on; do not guess. Stuck? Read the verify output first. It names the interface, neighbour or route that is wrong. Why this matters
Configure EIGRP the way the current syllabus writes it — a name, an address family, an af-interface — then use variance to install a SECOND path to the same prefix, one that is slower than the best. No other protocol here will do that.
What you will be able to do
R1 runs EIGRP in NAMED mode, as the process CORE
…in autonomous system 100, so it peers with the others
R1 learns R4’s loopback
Variance is set to at least 2 under topology base
The network
ISR 2921 — 4 devices in all, already cabled.
Gi0/1 10.0.12.1/30 Gi0/1 10.0.12.2/30 Gi0/2 10.0.13.1/30 Gi0/1 10.0.13.2/30 Gi0/2 10.0.24.1/30 Gi0/1 10.0.24.2/30 Gi0/2 10.0.34.1/30 Gi0/2 10.0.34.2/30 R1 R2 R3 R4 Drawn from this lab: devices, cables, ports and the addresses already set. Device Model Address already set
R1 ISR 2921 configure it R2 ISR 2921 configure it R3 ISR 2921 configure it R4 ISR 2921 configure it
Cabling
R1 Gi0/1 ↔ R2 Gi0/1 R1 Gi0/2 ↔ R3 Gi0/1 R2 Gi0/2 ↔ R4 Gi0/1 R3 Gi0/2 ↔ R4 Gi0/2
What is configured at the start
These are already configured when the lab opens — including, where this is a troubleshooting lab, the fault itself:
R1 interface GigabitEthernet0/1
ip address 10.0.12.1 255.255.255.252
no shutdown
exit
interface GigabitEthernet0/2
ip address 10.0.13.1 255.255.255.252
no shutdown
bandwidth 10000
exit R2 interface GigabitEthernet0/1
ip address 10.0.12.2 255.255.255.252
no shutdown
exit
interface GigabitEthernet0/2
ip address 10.0.24.1 255.255.255.252
no shutdown
exit
router eigrp 100
network 10.0.0.0 0.255.255.255 R3 interface GigabitEthernet0/1
ip address 10.0.13.2 255.255.255.252
no shutdown
bandwidth 10000
exit
interface GigabitEthernet0/2
ip address 10.0.34.1 255.255.255.252
no shutdown
bandwidth 10000
exit
router eigrp 100
network 10.0.0.0 0.255.255.255 R4 interface Loopback0
ip address 4.4.4.4 255.255.255.0
exit
interface GigabitEthernet0/1
ip address 10.0.24.2 255.255.255.252
no shutdown
exit
interface GigabitEthernet0/2
ip address 10.0.34.2 255.255.255.252
no shutdown
bandwidth 10000
exit
router eigrp 100
network 10.0.0.0 0.255.255.255
network 4.4.4.0 0.0.0.255 Tasks, and how each one is checked
Every task is decided by reading the live network — a neighbour in FULL, a ping that succeeds, a line in the running configuration — not by looking for a keyword you typed. The same command shows you what the lab sees.
# Task Pts How to verify it yourself
1 R1 runs EIGRP in NAMED mode, as the process CORE 25 Checked automatically against the device’s live state (eigrpNamed). 2 …in autonomous system 100, so it peers with the others 20 On R1: show ip eigrp neighbors shows at least 2 neighbour(s). 3 R1 learns R4’s loopback 15 On R1: show ip route lists 4.4.4.0/24. 4 Variance is set to at least 2 under topology base 20 Checked automatically against the device’s live state (variance). 5 …and TWO paths are installed for that one prefix 20 Checked automatically against the device’s live state (unequalPaths).
Stuck? Ask the coach
Tell the coach what you see or what you tried. It gives you a hint, not the answer, the way a senior engineer would. Included with a free trial or any plan.
Ask the coach
Reference solution
Try it yourself first — the lab checks your work either way. This is one configuration that makes every task pass, device by device:
R1 router eigrp CORE
address-family ipv4 unicast autonomous-system 100
topology base
variance 4
exit-af-topology
network 10.0.0.0 0.255.255.255
exit-address-family
exit Where this is examined
This lab practises these topics in the zNetLaB certification courses:
Related labs
Where to start
The lessons all guided labs plans
CCNA®, CCNP® and Cisco® are trademarks of Cisco Systems, Inc. zNetLaB is not affiliated with or endorsed by Cisco.