Introduction to IPv6

Configuration and Management

and the interface identifier currently in use in the link-local address. Having a global unicast address and a connection to an IPv6- aware router enables IPv6 traffic on a VLAN to be routed to other VLANs supporting IPv6-aware devices. (Using software release K.13.01, an external, IPv6- aware router is required to forward traffic between VLANs.)

Multiple, global unicast addresses can be configured on a VLAN that receives RAs specifying different prefixes.

DHCPv6 (Stateful) Address Configuration

The IPv6 counterpart to DHCP client for IPv4 operation is DHCPv6. Global unicast addresses of any scope can be assigned, along with NTP (timep) server addressing when DHCPv6 server support is available through either of the following modes:

■accessible on a VLAN configured on the switch

■accessible through a connection to a router configured with DHCP relay

IPv6 also allows the option of using stateless autoconfiguration or static configuration to assign unicast addresses to a VLAN, while using a DHCPv6 server for time server addressing.

Static Address Configuration

Statically configuring IPv6 addresses provides flexibility and control over the actual address values used on an interface. Also, if a statically configured link- local address is configured on a static VLAN, the global addresses configured on the VLAN as the result of router advertisements uses the device identifier included in the link-local address. Statically configuring an IPv6 address on a VLAN enables IPv6 on the VLAN if it has not already been enabled.

Default IPv6 Gateway

Instead of using static or DHCPv6 configuration, a default IPv6 gateway for an interface (VLAN) is determined from the default router list of reachable or probably reachable routers the switch detects from periodic multicast router advertisements (RAs) received on the interface. For a given interface, there can be multiple default gateways, with different nodes on the link using different gateways. If the switch does not detect any IPv6 routers that are reachable from a given interface, it assumes (for that interface) that it can reach only the other devices connected to the interface.

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