43-6
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 43 Configuring IPv6 Unicast Routing
Understanding IPv6
Figure 43-1 Dual IPv4 and IPv6 Support on an Interface
Use the dual IPv4 and IPv6 switch database management (SDM) template to enable IPv6 routing dual
stack environments (supporting both IPv4 and IPv6). For more information about the dual IPv4 and IPv6
SDM template, see Chapter 8, “Configuring SDM Templates.”
The dual IPv4 and IPv6 templates allow the switch to be used in dual stack environments.
• If you try to configure IPv6 without first selecting a dual IPv4 and IPv6 template, a warning message
appears.
• In IPv4-only environments, the switch routes IPv4 packets and applies IPv4 QoS and ACLs in
hardware. IPv6 packets are not supported.
• In dual IPv4 and IPv6 environments, the switch routes both IPv4 and IPv6 packets and applies IPv4
QoS in hardware.
• The switch supports QoS for both IPv4and IPv6 traffic.
• If you do not plan to use IPv6, do not use the dual stack template because this template results in
less hardware memory capacity for each resource.
For more information about IPv4 and IPv6 protocol stacks, see the “Implementing IPv6 Addressing and
Basic Connectivity” chapter of Cisco IOS IPv6 Configuration Library on Cisco.com.
DHCP for IPv6 Address Assignment
DHCPv6 enables DHCP servers to pass configuration parameters, such as IPv6 network addresses, to
IPv6 clients. The address assignment feature manages non duplicate address assignment in the correct
prefix based on the network where the host is connected. Assigned addresses can be from one or multiple
prefix pools. Additional options, such as default domain and DNS name-server address, can be passed
back to the client. Address pools can be assigned for use on a specific interface, on multiple interfaces,
or the server can automatically find the appropriate pool.
This document describes only the DHCPv6 address assignment. For more information about configuring
the DHCPv6 client, server, or relay agent functions, see the “Implementing DHCP for IPv6” chapter in
the Cisco IOS IPv6 Configuration Library on Cisco.com.
Static Routes for IPv6
Static routes are manually configured and define an explicit route between two networking devices.
Static routes are useful for smaller networks with only one path to an outside network or to provide
security for certain types of traffic in a larger network.
122379
3ffe:yyyy::1
10.1.1.1
IPv6
IPv4