IPv6 Routing and Configuration

Overview

This lecture covers configuring IPv6 static routes, including main and backup paths, enabling router IPv6 routing, using SLAAC for PC configuration, and introduces RIPng for dynamic IPv6 routing on Cisco devices.

Enabling IPv6 Routing and Addressing

• IPv6 routing must be enabled on each router using ipv6 unicast-routing.
• PCs obtain IPv6 addresses and default gateways automatically via SLAAC (Stateless Address Autoconfiguration).
• SLAAC uses NDP router advertisement messages and generates interface IDs with EUI-64.

Configuring IPv6 Static Routes

• Static routes are required for communication between PC1 (behind R1) and PC2 (behind R3).
• Main route uses the direct R1–R3 connection; backup route goes through R2.
• On Ethernet interfaces, use fully specified static routes (interface + next hop).
• Floating static routes use a higher administrative distance (AD) to provide backup paths.

Using Link-Local Addresses in Static Routes

• Link-local addresses are used as next hops on serial interfaces without global IPv6 addresses.
• When specifying a link-local next hop, always include the exit interface.

Verifying Configuration and Connectivity

• Use show ipv6 route to verify static routes in the routing table.
• Use show run | include ipv6 route to filter and view configured routes.
• Ping and traceroute commands check connectivity and path taken by packets.

RIPng (Routing Information Protocol Next Generation) for IPv6

• RIPng can share IPv6 routes dynamically, though it's not on the CCNA exam.
• Enable RIPng globally with ipv6 router rip <process-name>.
• Activate RIPng on interfaces using ipv6 rip <process-name> enable.
• After enabling, routers advertise/learn routes, enabling pings to remote loopback interfaces.
• Use show ipv6 protocols and show ipv6 route to verify RIPng status and learned routes.

Key Terms & Definitions

• SLAAC — IPv6 Stateless Address Autoconfiguration; allows devices to self-configure addresses with info from router advertisements.
• NDP — Neighbor Discovery Protocol for IPv6; handles address autoconfiguration and discovery.
• EUI-64 — Method to create a 64-bit interface ID from a MAC address.
• Floating Static Route — Backup static route with higher administrative distance than primary route.
• Administrative Distance (AD) — Trustworthiness value for a route; lower AD is preferred.
• RIPng — Routing Information Protocol next generation; a dynamic IPv6 routing protocol.

Action Items / Next Steps

• Complete configuring IPv6 addresses on all routers and loopback interfaces for Task 1.
• Enable and verify RIPng on all interfaces for Task 2.
• Configure and test connectivity between Router1 and Router3 for Task 3.
• Use provided lab files and Packet Tracer or NetSim for hands-on practice.