4.2 EIGRP for IPv6 Overview

CCNP RS 300-101, Configuring EIGRP for IPv6, Uncategorized
Key differences between EIGRP for version 4 and version 6

Key differences between IPv4 and IPv6, explained:

  • IPv6 uses link-local EUI-64 addressing to form neighbor relationships (using hellos, similar to IPv4). IPv4 has no concept of link-local addressing.
  • While both protocols support the assignment of a 32-bit router ID to function, it is required to be configured in IPv6 (but not required in IPv4).
  • Both protocols support injection of summary routes, but IPv6 does not support the auto-summary command. This is only available in IPv4.
  • To enable the protocol on an interface in IPv6, you define it on the interface itself. There is no configuration of passive interfaces as in IPv4; just don’t define it on an interface (advertisement and participating are one in the same in IPv6).
  • EIGRPv6 uses built-in authentication features of IPv6 rather than EIGRP-specific authentication commands as seen in IPv4.
  • Multicast addresses for membership are obviously different, but they each equate to “10” (EIGRPv6 = FF:02::A, EIGRP = 224.0.0.10)

Requirements for EIGRPv6 operation:

  • Enable the EIGRPv6 protocol globally:

ipv6 unicast-routing

  • Define the EIGRP section, as with IPv4 using the following syntax:

ipv6 router eigrp <AS#>

  • You MUST configure a router ID in the EIGRP section (if there is an IPv4 address on the router, it will actually use that, but best practice is to configure the router-ID for EIGRPv6).

eigrp router-id <router ID, ex: 192.168.1.1>

  • The routing protocol must be explicitly enabled via the no shutdown command:

no shutdown

  • Finally, there is no network command to enable EIGRPv6 on an interface. It is defined on the interface itself using the following command in interface configuration mode:

ipv6 eigrp <AS#>

Published