IPv6 Addressing Configuration

Disabling IPv6 on a VLAN

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Duplicate Address Detection (DAD) for Statically Configured Addresses

Statically configured IPv6 addresses are designated as permanent. If DAD determines that a statically configured address duplicates a previously config­ ured and reachable address on another device belonging to the VLAN, then the more recent, duplicate address is designated as duplicate. For more on this topic, refer to:

■“Duplicate Address Detection (DAD)” on page 4-18.

■“View the Current IPv6 Addressing Configuration” on page 4-21

Multiple, duplicate addresses configured as Anycast on different devices are special cases of unicast addresses, and are not identified as duplicates by DAD. Refer to “Anycast Addresses” on page 3-20.

Disabling IPv6 on a VLAN

While one IPv6-enabling command is configured on a VLAN, IPv6 remains enabled on that VLAN. In this case, removing the only IPv6-enabling command from the configuration disables IPv6 operation on the VLAN. That is, to disable IPv6 on a VLAN, all of the following commands must be removed from the VLAN's configuration:

ipv6 enable

ipv6 address dhcp full [rapid-commit] ipv6 address autoconfig

ipv6 address fe80::< device-identifier> link-local ipv6 address < prefix > : < device-identifier>

If any of the above remain enabled, then IPv6 remains enabled on the VLAN and, at a minimum, a link-local unicast address will be present.

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