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Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter39 Configuring IPv6 Unicast Routing
Configuring IPv6
Configuring IPv4 and IPv6 Protocol Stacks
Before configuring IPv6 routing, you must select an SDM template that supports IPv4 and IPv6. If not
already configured, use the sdm prefer dual-ipv4-and-ipv6 {default | routing | vlan} [desktop] global
configuration command to configure a template that supports IPv6. When you select a new template, you
must reload the switch by using the reload privileged EXEC command so that the template takes effect.
Beginning in privileged EXEC mode, follow these steps to configure a Layer 3 interface to support both
IPv4 and IPv6 and to enable IPv6 routing.
To disable IPv4 routing, use the no ip routing global configuration command. To disable IPv6 routing,
use the no ipv6 unicast-routing global configuration command. To remove an IPv4 address from an
interface, use the no ip address ip-address mask interface configuration command. To remove an IPv6
address from an interface, use the no ipv6 address ipv6-prefix/prefix length eui-64 or no ipv6 address
ipv6-address link-local interface configuration command. To remove all manually configured IPv6
addresses from an interface, use the no ipv6 address interface configuration command without
arguments. To disable IPv6 processing on an interface that has not been explicitly configured with an
IPv6 address, use the no ipv6 enable interface configuration command.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip routing Enable routing on the switch.
Step3 ipv6 unicast-routing Enable forwarding of IPv6 data packets on the switch.
Step4 interface interface-id Enter interface configuration mode, and specify the Layer 3
interface to configure.
Step5 no switchport Remove the interface from Layer 2 configuration mode (if it is a
physical interface).
Step6 ip address ip-address mask [secondary] Specify a primary or secondary IPv4 address for the interface.
Step7 ipv6 address ipv6-prefix/prefix length eui-64
or
ipv6 address ipv6-address link-local
or
ipv6 enable
Specify a global IPv6 address. Specify only the network prefix;
the last 64 bits are automatically computed from the switch
MAC address.
Specify a link-local address on the interface to be used instead
of the automatically configured link-local address when IPv6 is
enabled on the interface.
Automatically configure an IPv6 link-local address on the
interface, and enable the interface for IPv6 processing. The
link-local address can only be used to communicate with nodes
on the same link.
Step8 end Return to privileged EXEC mode.
Step9 show interface interface-id
show ip interface interface-id
show ipv6 interface interface-id
Verify your entries.
Step10 copy running-config startup-config (Optional) Save your entries in the configuration file.