What is EIGRP named mode, and why would you use it instead of classic mode?
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Say this first
Named mode puts all EIGRP configuration under one router eigrp NAME block, with address families
for IPv4 and IPv6, per-interface settings in af-interface sections instead of scattered across
interfaces, and routing policy under topology base. It is the only mode with 64-bit wide metrics, it
supports HMAC-SHA-256 authentication, and af-interface default sets passive, timers or authentication
once for every interface. The name is local; the AS number must still match the neighbor.
Go deeper
Same intent, both modes
Classic:
interface GigabitEthernet0/0/0
ip hello-interval eigrp 100 2
ip hold-time eigrp 100 6
!
router eigrp 100
network 10.0.0.0 0.255.255.255
passive-interface default
no passive-interface GigabitEthernet0/0/0
variance 2
eigrp router-id 10.255.0.1Named:
router eigrp CAMPUS
address-family ipv4 unicast autonomous-system 100
af-interface default
passive-interface
exit-af-interface
af-interface GigabitEthernet0/0/0
no passive-interface
hello-interval 2
hold-time 6
exit-af-interface
topology base
variance 2
exit-af-topology
network 10.0.0.0 0.255.255.255
eigrp router-id 10.255.0.1
exit-address-familyWhere things live in named mode
| Section | Holds |
|---|---|
| address-family | network, eigrp router-id, eigrp stub |
| af-interface | hello and hold, passive, authentication, summary-address, split-horizon, bfd |
| topology base | variance, maximum-paths, redistribute, distance, summary-metric |
Show commands
Named mode has its own: show eigrp address-family ipv4 neighbors and
show eigrp address-family ipv4 topology. The classic show ip eigrp commands still work as well.
They will ask next
Can you convert a classic config to named mode without an outage?
Yes. Under the classic process,
eigrp upgrade-cli CAMPUSrewrites the configuration into named mode in place without resetting neighbors. Save and review the result afterwards.Can a named mode router peer with a classic mode router?
Yes, as long as the AS number and K values match. Mixing the two during a migration is normal.
Traps
- Thinking the name has to match on both routers. Only the AS number is exchanged.