Setup Guide
the same IPv6 address to a particular computer, and never to assign that IP address to another computer. This allows static IPv6 addresses
to be congured in one place, without having to specically congure each computer on the network in a dierent way.
In IPv6, every interface, whether using static or dynamic address assignments, also receives a local-link address automatically in the
fe80::/64 subnet.
Implementing IPv6 with Dell EMC Networking OS
Dell EMC Networking OS supports both IPv4 and IPv6 and both may be used simultaneously in your system.
ICMPv6
ICMP for IPv6 combines the roles of ICMP, IGMP and ARP in IPv4. Like IPv4, it provides functions for reporting delivery and forwarding
errors, and provides a simple echo service for troubleshooting. The Dell EMC Networking OS implementation of ICMPv6 is based on RFC
4443.
Generally, ICMPv6 uses two message types:
• Error reporting messages indicate when the forwarding or delivery of the packet failed at the destination or intermediate node. These
messages include Destination Unreachable, Packet Too Big, Time Exceeded and Parameter Problem messages.
• Informational messages provide diagnostic functions and additional host functions, such as Neighbor Discovery and Multicast Listener
Discovery. These messages also include Echo Request and Echo Reply messages.
The Dell EMC Networking OS ping and traceroute commands extend to support IPv6 addresses. These commands use ICMPv6
Type-2 messages.
Path MTU discovery
The size of the packet that can be sent across each hop in the network path without being fragmented is called the path maximum
transmission unit (PMTU). The PMTU value might dier for the same route between two devices, mainly over a public network, depending
on the network load and speed, and it is not a consistent value. The MTU size can also be dierent for various types of trac sent from
one host to the same endpoint.
Path MTU discovery (PMTD) identies the path MTU value between the sender and the receiver, and uses the determined value to
transmit the packets across the network. Path MTU, in accordance with RFC 1981, denes the largest packet size that can traverse a
transmission path without suering fragmentation. Path MTU for IPv6 uses ICMPv6 Type-2 messages to discover the largest MTU along
the path from source to destination and avoid the need to fragment the packet. The recommended MTU for IPv6 is 1280. Greater MTU
settings increase the processing eciency because each packet carries more data while protocol overheads (for example, headers) or
underlying per-packet delays remain xed.
IPv6 Routing
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