Since IOS 15, EIGRP has a new method of configuration called named mode EIGRP. With the “classic” version of EIGRP that we used before IOS 15 we configured EIGRP globally and some other things (like authentication) on the interfaces. With named mode EIGRP, we do everything globally.
If you try to configure EIGRP on a IOS 15.x router you will see this:
R1(config)#router eigrp ? <1-65535> Autonomous System WORD EIGRP Virtual-Instance Name
Instead of an AS number we can also choose a name. Let’s try this, I’ll use two routers for this demonstration:
Let’s start with R1:
R1(config)#router eigrp MY_NAME R1(config-router)#? Router configuration commands: address-family Enter Address Family command mode default Set a command to its defaults exit Exit from routing protocol configuration mode no Negate a command or set its defaults service-family Enter Service Family command mode shutdown Shutdown this instance of EIGRP
The configuration is now done using an address-family. Let’s select it:
R1(config-router)#address-family ? ipv4 Address family IPv4 ipv6 Address family IPv6
EIGRP named mode covers both IPv4 and IPv6. Let’s try IPv4:
R1(config-router)#address-family ipv4 autonomous-system 12
This is where I configure everything. For example advertising a network:
Everything that used to be configured on the interface is now under the same global configuration:
R1(config-router-af)#af-interface FastEthernet 0/0 R1(config-router-af-interface)#? Address Family Interfaces configuration commands: authentication authentication subcommands bandwidth-percent Set percentage of bandwidth percentage limit bfd Enable Bidirectional Forwarding Detection dampening-change Percent interface metric must change to cause update dampening-interval Time in seconds to check interface metrics default Set a command to its defaults exit-af-interface Exit from Address Family Interface configuration mode hello-interval Configures hello interval hold-time Configures hold time next-hop-self Configures EIGRP next-hop-self no Negate a command or set its defaults passive-interface Suppress address updates on an interface shutdown Disable Address-Family on interface split-horizon Perform split horizon summary-address Perform address summarization
Let’s try authentication:
I agree, it’s nice to configure everything under 1 process.
what is address-family?
The address-family is the “protocol” that the routing protocol supports. In this example, EIGRP supports IPv4 and IPv6.
Another example is MP-BGP (Multi Protocol BGP). It supports multiple protocols:
- IPv4 unicast
- IPv4 multicast
- IPv6 unicast
- IPv6 multicast
- VPN Routes (for MPLS)
Each of these different “protocols” are configured under a different address-family.
with named mode, are we supposed to do route summary at interface level (old style) or it is should be done under af-interface?