Quick Reference Guide

62 PowerConnect B-Series TI24X Configuration Guide

53-1002269-02

IPv6 CLI command support

IPv6 stateless autoconfiguration

PowerConnect devices use the IPv6 stateless autoconfiguration feature to enable a host on a local

link to automatically configure its interfaces with new and globally unique IPv6 addresses

associated with its location. The automatic configuration of a host interface is performed without

the use of a server, such as a Dynamic Host Configuration Protocol (DHCP) server, or manual

configuration.

The automatic configuration of a host interface works in the following way: a switch on a local link

periodically sends switch advertisement messages containing network-type information, such as

the 64-bit prefix of the local link and the default route, to all nodes on the link. When a host on the

link receives the message, it takes the local link prefix from the message and appends a 64-bit

interface ID, thereby automatically configuring its interface. (The 64-bit interface ID is derived from

the MAC address of the host NIC.) The 128-bit IPv6 address is then subjected to duplicate address

detection to ensure that the address is unique on the link.

The duplicate address detection feature verifies that a unicast IPv6 address is unique before it is

assigned to a host interface by the stateless auto configuration feature. Duplicate address

detection uses neighbor solicitation messages to verify that a unicast IPv6 address is unique.

NOTE

For the stateless auto configuration feature to work properly, the advertised prefix length in switch

advertisement messages must always be 64 bits.

The IPv6 stateless autoconfiguration feature can also automatically reconfigure a host interfaces if

you change the ISP for the host network. (The host interfaces must be renumbered with the IPv6

prefix of the new ISP.)

The renumbering occurs in the following way: a switch on a local link periodically sends

advertisements updated with the prefix of the new ISP to all nodes on the link. (The advertisements

still contain the prefix of the old ISP.) A host can use the addresses created from the new prefix and

the existing addresses created from the old prefix on the link. During this transition, the old prefix is

removed from the switch advertisements. At this point, only addresses that contain the new prefix

are used on the link.

IPv6 CLI command support

Table 13 lists the IPv6 CLI commands supported.

TABLE 13 IPv6 CLI command support

IPv6 command Description Switch code Router code

clear ipv6 cache Deletes all entries in the dynamic host cache. X

clear ipv6 neighbor Deletes all dynamic entries in the IPv6 neighbor

table.

clear ipv6 traffic Resets all IPv6 packet counters. X X

copy tftp Downloads a copy of a Dell software image from a

TFTP server into the system flash using IPv6.

debug ipv6 Displays IPv6 debug information. X X

ipv6 address Configures an IPv6 address on an interface

(router) or globally (switch)