IPv6 Addressing Configuration

Enabling IPv6 with an Automatically Configured Link-Local Address

Enabling IPv6 with an AutomaticallyConfigured Link-Local Address

This command enables automatic configuration of a link-local address.

Syntax: [no] ipv6 enable

If IPv6 has not already been enabled on a VLAN by another IPv6 command option described in this chapter, this command enables IPv6 on the VLAN and automatically configures the VLAN's link-local unicast address with a 64-bit EUI-64 inter­ face identifier generated from the VLAN MAC address. (Refer to “Extended Unique Identifier (EUI)” on page 3-14.).

Note: Only one link-local IPv6 address is allowed on the VLAN interface. Subsequent static or DHCP configuration of another link-local address overwrites the existing link- local address.

A link-local address always uses the prefix fe80:0:0:0.

With IPv6 enabled, the VLAN uses received router advertise­ ments to designate the default IPv6 router. (Refer to “Default IPv6 Router” on page 4-28.)

After verification of uniqueness by DAD, a link-local IPv6 address assigned automatically is set to the preferred status, with a “permanent” lifetime. (Refer to “IPv6 Address Depreca­ tion” on page 3-25.)

Default: Disabled

The no form of the command disables IPv6 on the VLAN if no other IPv6-enabling command is configured on the VLAN. (Refer to “Disabling IPv6 on a VLAN” on page 4-16.)

To view the current IPv6 Enable setting and any statically configured IPv6 addresses per-VLAN, use show run.

To view all currently configured IPv6 unicast addresses, use the following:

■show ipv6 (Lists IPv6 addresses for all VLANs configured on the switch.)

■show ipv6 vlan < vid > (Lists IPv6 addresses configured on the VLAN.)

For more information, refer to “View the Current IPv6 Addressing Configura­ tion” on page 4-21.

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