Reference Guide

The router redirect functionality in the Neighbor Discovery protocol (NDP) is similar to IPv4 router redirect messages. NDP uses ICMPv6
redirect messages (Type 137) to inform nodes that a better router exists on the link.
IPv6 addresses
An IPv6 address consists of a 48-bit global routing prex, optional 16-bit subnet ID (referred to as the site-level aggregator or SLA), and a
64-bit interface identier in the extended universal identier (EUI)-64 format.
IPv6 128-bit addresses are represented as a series of eight 16-bit hexadecimal elds separated by colons in the format: n:n:n:n:n:n:n:n. This
is an example of an IPv6 address:
2001:0db8:0000:0000:0000:0000:1428:57a
Leading zeros in each eld are optional. You can also use two colons (::) to represent successive hexadecimal elds of zeros, but you can
use this short version only once in each address:
2001:db8::1428:57ab
In the following example, all the addresses are valid and equivalent:
• 2001:0db8:0000:0000:0000:0000:1428:57ab
• 2001:0db8:0000:0000:0000::1428:57ab
•
2001:0db8:0:0:0:0:1428:57ab
• 2001:0db8:0:0::1428:57ab
• 2001:0db8::1428:57ab
• 2001:db8::1428:57ab
IPv6 networks are written using CIDR notation. An IPv6 network (or subnet) is a contiguous group of IPv6 addresses the size of which
must be a power of two. The initial bits of addresses, which are identical for all hosts in the network, are called the network's prex.
A network is denoted by the rst address in the network and the size in bits of the prex (in decimal), separated with a slash. Because a
single host is seen as a network with a 128-bit prex, host addresses may be written with a following /128.
For example, 2001:0db8:1234::/48 stands for the network with addresses 2001:0db8:1234:0000:0000:0000:0000:0000
through 2001:0db8:1234:ffff:ffff:ffff:ffff:ffff.
As soon as an IPv6 address is assigned, IPv6 packet processing is enabled on an interface.
Link-local addresses
When an OS10 switch boots up, an IPv6 unicast link-local address is automatically assigned to an interface using stateless conguration. A
link-local address allows IPv6 devices on a local link to communicate without requiring a globally unique address.
A link-local address autocongures using the prex FE80::/10 received from a neighboring IPv6 device on a local link, and generates an
interface identier in EUI-64 format using the interface's MAC address. IPv6 reserves the address block FE80::/10 for link-local unicast
addressing.
DHCP-assigned addresses
An IPv6 address can also be automatically assigned using a DHCP server (ipv6 address dhcp command). A DHCPv6 server uses a
prex pool to congure a network address on an interface. The interface ID is automatically generated.
Manally congured addresses
An interface can have multiple IPv6 addresses. To congure an IPv6 address in addition to the link-local address, enter the ipv6
address
ipv6-address/mask command. You only need to specify the network prex because the 64-bit interface ID is automatically
calculated from the MAC address.
Layer 3
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