NHPREP — Hands-On CCNA, CCNP, CCIE Labs & Networking Courses

Lab Objectives

Configure EIGRP in named mode using address families on the routers in the topology.
Verify EIGRP adjacency and route propagation; compare named mode behavior with classic EIGRP.
Understand why named mode is useful and when to use it in production networks.

IP SCHEME

10.10.10.0/24 — R1-R2 link
10.10.20.0/24 — R1-R3 link
10.10.30.0/24 — R1-R4 link
10.10.40.0/24 — R2-S1 link
192.168.1.0/24 — VLAN 10 (Sales)
192.168.2.0/24 — VLAN 20 (Engineering)
192.168.3.0/24 — VLAN 30 (Management)
203.0.113.0/24 — Public/Internet simulation

Tip: Think of EIGRP named mode like moving from a single language CLI to a locale-aware CLI: you group EIGRP configuration by address family so IPv4 and IPv6 settings live cleanly under the same process name.

Lab Tasks (Try It Yourself First!)

Complete these tasks WITHOUT looking at the solution below. Use ? and show commands to figure it out.

Task 1: Configure EIGRP Named Mode

On each router (R1, R2, R3, R4) create an EIGRP named instance called "NHPREP" using autonomous system 100. Under the IPv4 address family, advertise each router's directly connected /24 links (10.10.10.0/24, 10.10.20.0/24, 10.10.30.0/24, 10.10.40.0/24). Disable automatic summarization.

Task 2: Verify Adjacency and Routes

On R1, verify EIGRP neighbors and the EIGRP routes learned from R2, R3, R4. Confirm R1 sees 10.10.40.0/24 (via R2) in its routing table.

Task 3: Compare with Classic EIGRP

On R1 only, show the equivalent classic EIGRP configuration that advertises the same networks using ASN 100. Observe configuration differences between named and classic modes and note how to inspect each in the running configuration.

Think About It: Why might a service provider or large enterprise prefer named-mode EIGRP over classic mode when supporting both IPv4 and IPv6 in the same device?

Lab Solution

Task 1 Solution: Configure EIGRP Named Mode

What we are doing: Create a named EIGRP process "NHPREP", enter the IPv4 address-family, advertise connected /24 networks with wildcard masks, and disable auto-summary so routes are not auto-summarized across major network boundaries. This groups IPv4 settings under one named process and prepares for optional IPv6 address-family later.

R1 configuration:

R1(config)# router eigrp NHPREP
R1(config-router)# address-family ipv4 unicast autonomous-system 100
R1(config-router-af)# network 10.10.10.0 0.0.0.255
R1(config-router-af)# network 10.10.20.0 0.0.0.255
R1(config-router-af)# network 10.10.30.0 0.0.0.255
R1(config-router-af)# no auto-summary
R1(config-router-af)# no shutdown
R1(config-router-af)# exit-address-family

R2 configuration:

R2(config)# router eigrp NHPREP
R2(config-router)# address-family ipv4 unicast autonomous-system 100
R2(config-router-af)# network 10.10.10.0 0.0.0.255
R2(config-router-af)# network 10.10.40.0 0.0.0.255
R2(config-router-af)# no auto-summary
R2(config-router-af)# no shutdown
R2(config-router-af)# exit-address-family

R3 configuration (interface toward R1 assumed 10.10.20.2):

R3(config)# router eigrp NHPREP
R3(config-router)# address-family ipv4 unicast autonomous-system 100
R3(config-router-af)# network 10.10.20.0 0.0.0.255
R3(config-router-af)# no auto-summary
R3(config-router-af)# no shutdown
R3(config-router-af)# exit-address-family

R4 configuration:

R4(config)# router eigrp NHPREP
R4(config-router)# address-family ipv4 unicast autonomous-system 100
R4(config-router-af)# network 10.10.30.0 0.0.0.255
R4(config-router-af)# no auto-summary
R4(config-router-af)# no shutdown
R4(config-router-af)# exit-address-family

What just happened:

router eigrp NHPREP creates a named EIGRP process called NHPREP. Named mode groups multiple address families (IPv4/IPv6).
address-family ipv4 unicast autonomous-system 100 enters the IPv4 address-family and binds it to ASN 100 — equivalent to classic router eigrp 100 for IPv4.
network <ip> <wildcard> tells EIGRP which connected networks to advertise and on which interfaces to form adjacencies.
no auto-summary prevents summarizing networks at classful boundaries (important in modern networks where discontiguous subnets exist).
no shutdown enables the address-family (named mode defaults may be administratively down until enabled).

Verify:

R1# show ip eigrp neighbors
IP-EIGRP neighbors for process NHPREP (100)
H   Address         Interface       Hold Uptime   SRTT  RTO  Q  Seq
0   10.10.10.2      Gi0/0           12   00:05:10  20    500  0  12
1   10.10.20.2      Gi0/1           14   00:05:05  22    500  0  22
2   10.10.30.2      Gi0/2           11   00:05:02  18    500  0  32

R1# show running-config | section router eigrp
router eigrp NHPREP
 address-family ipv4 unicast autonomous-system 100
  network 10.10.10.0 0.0.0.255
  network 10.10.20.0 0.0.0.255
  network 10.10.30.0 0.0.0.255
  no auto-summary
  no shutdown
 exit-address-family

Task 2 Solution: Verify Adjacency and Routes

What we are doing: Confirm EIGRP neighbors are established and routes from R2, R3, R4 are present in R1's routing table.

R1# show ip route eigrp
Codes: C - connected, S - static, R - RIP, M - OSPF, D - EIGRP, EX - EIGRP external
D 10.10.40.0/24 [90/3072] via 10.10.10.2, 00:05:10, GigabitEthernet0/0
D 10.10.20.0/24 [90/3072] via 10.10.20.2, 00:05:05, GigabitEthernet0/1
D 10.10.30.0/24 [90/3072] via 10.10.30.2, 00:05:02, GigabitEthernet0/2

R1# show ip eigrp topology
IP-EIGRP (AS100) Topology Table for process NHPREP
Codes: P - Passive, A - Active
P 10.10.40.0/24, 1 successors, FD is 2816000
 via 10.10.10.2 (2816000/3072), GigabitEthernet0/0
P 10.10.20.0/24, 1 successors, FD is 2816000
 via 10.10.20.2 (2816000/3072), GigabitEthernet0/1
P 10.10.30.0/24, 1 successors, FD is 2816000
 via 10.10.30.2 (2816000/3072), GigabitEthernet0/2

What just happened:

show ip route eigrp shows routes learned via EIGRP (marked D). R1 learns 10.10.40.0/24 via R2 — demonstrating route propagation across the EIGRP domain.
show ip eigrp topology shows candidate successors (used for loop-free backups) and the feasible distance/metric.

Real-world context: In a data center or branch environment, seeing these routes means the routers will forward traffic between subnets without static routes, enabling scalable network growth.

Task 3 Solution: Compare with Classic EIGRP

What we are doing: Show the equivalent classic EIGRP configuration on R1 using router eigrp 100 and the classic network statements. Compare visible differences.

Classic EIGRP config on R1 (equivalent to above IPv4 behavior):

R1(config)# no router eigrp NHPREP
R1(config)# router eigrp 100
R1(config-router)# network 10.10.10.0 0.0.0.255
R1(config-router)# network 10.10.20.0 0.0.0.255
R1(config-router)# network 10.10.30.0 0.0.0.255
R1(config-router)# no auto-summary

What just happened:

Classic router eigrp 100 creates an ASN-bound process for IPv4 only. Named mode uses router eigrp <name> and then per-address-family configuration.
With named mode, IPv4 configuration sits under address-family ipv4 unicast which helps when configuring IPv6 or multiple address families under the same process name.
Use show running-config | section router eigrp to see whether named or classic is configured. They are configured differently in the running-config.

Verify:

R1# show running-config | section router eigrp
router eigrp 100
 network 10.10.10.0 0.0.0.255
 network 10.10.20.0 0.0.0.255
 network 10.10.30.0 0.0.0.255
 no auto-summary
!

Important: Named mode is preferred when you plan to manage both IPv4 and IPv6 EIGRP under one named process or want clearer configuration segregation. Classic mode remains supported for IPv4-only scenarios.

Troubleshooting Scenario

Scenario: R2 is not advertising the 10.10.40.0/24 network

Symptom: Ping from a host in 10.10.40.0/24 (PC on S1) to a host in 10.10.30.0/24 fails. R1 does not have a route to 10.10.40.0/24.

Your task: Find and fix the issue.

Hint: Check what networks are advertised under the EIGRP address-family on R2.

Solution:

Problem: R2's named EIGRP configuration omitted the network 10.10.40.0 0.0.0.255 statement, so the 10.10.40.0/24 network was not advertised.
Fix on R2:

R2(config)# router eigrp NHPREP
R2(config-router)# address-family ipv4 unicast autonomous-system 100
R2(config-router-af)# network 10.10.40.0 0.0.0.255
R2(config-router-af)# no shutdown
R2(config-router-af)# exit-address-family

Verify:

R1# show ip route eigrp
D 10.10.40.0/24 [90/3072] via 10.10.10.2, 00:00:20, GigabitEthernet0/0

Explanation: Without the network statement, EIGRP will not advertise the subnet and will not form adjacency on interfaces that are not matched by any network statement.

Verification Checklist

EIGRP named process "NHPREP" exists on R1–R4.
address-family ipv4 unicast autonomous-system 100 configured and no auto-summary applied.
All routers show EIGRP neighbors (show ip eigrp neighbors).
R1 contains D routes for 10.10.20.0/24, 10.10.30.0/24, and 10.10.40.0/24 (show ip route eigrp).

Common Mistakes

Symptom	Cause	Fix
No EIGRP neighbors on R1	Forgot to add a `network` under the IPv4 address-family on a neighbor	Add matching `network <net> 0.0.0.255` under `address-family ipv4` and `no shutdown`
Routes not appearing	`no auto-summary` missing causing unexpected summarization (in discontiguous networks)	Configure `no auto-summary` under the address-family
Named config not visible	Looking for `router eigrp 100` instead of `router eigrp <name>`	Use `show running-config
Attempting to configure IPv6 under classic EIGRP	Classic is IPv4-only	Use named mode and `address-family ipv6` for IPv6 configuration

Challenge Task

Convert the network to run EIGRP named mode supporting both IPv4 and IPv6 simultaneously under the same named process. Configure a link-local IPv6 address on the R1–R2 interface and advertise a sample IPv6 subnet in the IPv6 address-family for EIGRP. (No step-by-step provided — design and implement the address-family ipv6 configuration.)

Final thought: Named mode is cleaner and future-proof when you expect multi-protocol routing or want clearer separation of per-protocol settings. In production, elected use cases include routers that must run both IPv4 and IPv6 EIGRP or when you need distinct policy settings per address family.