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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.
Longest Prefix Match (LPM) Table and IPv6 /65
/128 support
The LPM CAM table consists of two partitions: Partition I for IPv6 /65-/128 route-prefix entries and Partition II for IPv6
0/0-/64 and IPv4 0/0-0/32 route-prefix entries. You must reconfigure LPM CAM to allow IPv6 /65-/128 route prefixes to be
stored in Partition I.
Use the cam-ipv6 extended-prefix command to enable IPv6 /65-/128 route prefixes to be stored in LPM CAM
Partition 1. You must specify the maximum number of IPv6 prefixes with /65-/128 mask length that are supported in the
partition. The valid values are 1024, 2048 or 3072 prefixes. You must save the configuration and reload the switch for the
change to take effect.
The number of entries in Partition II is reduced as the number of entries in Partition I increases.
To disable LPM CAM partitioning and return the number of the IPv6 /65-/128 route prefixes stored in Partition 1 to 0, enter
the no cam-ipv6 extended-prefix command.
Use the show cam-ipv6 extended-prefix command to display the currently configured number of IPv6 /65-/128
prefixes that can be stored in LPM CAM Partition 1 and the number that are supported after the next switch reboot.
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
Path MTU, in accordance with RFC 1981, defines the largest packet size that can traverse a transmission path without suffering
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 processing efficiency because each packet carries
more data while protocol overheads (for example, headers) or underlying per-packet delays remain fixed.
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IPv6 Routing