ipv6

interface-config-ge-instance

Sets the DHCPv6 and ICMPv6 ND (neighbor discovery) components for this interface

The ICMPv6 ND protocol uses ICMP messages and solicited multicast addresses to track neighboring devices on the same local network. These messages are used to discover a neighbor‘s link layer address and to verify if a neighboring device is reachable.

The ICMP messages are NS (neighbor solicitation) and NA (neighbor advertisement) messages. When a destination host receives an NS message from a neighbor, it replies back with a NA. The NA contains the following information:

  • Source address – This is the IPv6 address of the device sending the NA
  • Destination address – This is the IPv6 address of the device from whom the NS message is received
  • Data portion – Includes the link layer address of the device sending the NA

NS messages are used to verify a neighbor‘s (whose ink layer address is known) reachability. To confirm a neighbor‘s reachability a node sends an NS message in which the neighbor‘s unicast address is specified as the destination address. If the neighbor sends back an acknowledgment on receipt of the NS message it is considered reachable.

Supported in the following platforms:

  • Access Points — AP505i, AP510i/e, AP560i/h
  • Service Platforms — NX5500, NX7500, NX9500, NX9600, VX9000

Syntax

ipv6 [dhcpv6|nd]
ipv6 dhcpv6 trust
ipv6 nd [header-mismatch-validation|raguard|trust]

Parameters

ipv6 dhcpv6 trust
ipv6 dhcpv6 trust Enables trust state for DHCPv6 responses on this interface. When enabled, all DHCPv6 responses received on this port are trusted and forwarded. This option is enabled by default.

A DHCPv6 server can be connected to a DHCPv6 trusted port.

ipv6 nd [header-mismatch-validation|raguard|trust]
ipv6 nd Configures IPv6 ND settings
header-mismatch-validation Enables matching of source MAC address in the ICMPv6 ND and Ethernet headers (link layer option) to check for mismatch. This option is disabled by default.
raguard Allows redirection of RAs (router advertisements) and ICMPv6 packets originating on this interface. When selected, RAs are periodically sent to hosts or sent in response to neighbor solicitation requests. The advertisement includes IPv6 prefixes and other subnet and host information. This option is enabled by default.
trust Enables trust state for IPv6 ND requests received on this interface. When enabled, IPv6 hosts can configure themselves automatically when connected to an IPv6 network using the neighbor discovery protocol via ICMPv6 router discovery messages. When first connected to a network, a host sends a link-local router solicitation multicast request for its configuration parameters; routers respond to the request with a router advertisement packet containing Internet Layer configuration parameters. This option is disabled by default.

Example

nx9500-6C8809(config-device-B4-C7-99-6D-CD-4B-if-ge1)#ipv6 dhcpv6 trust

nx9500-6C8809(config-device-B4-C7-99-6D-CD-4B-if-ge1)#ipv6 nd header-mismatch-validation
nx9500-6C8809(config-device-B4-C7-99-6D-CD-4B-if-ge1)#ipv6 nd trust

nx9500-6C8809(config-device-B4-C7-99-6D-CD-4B-if-ge1)#show context
interface ge1
  switchport mode access
  switchport access vlan 1
  ipv6 nd trust
  ipv6 nd header-mismatch-validation
  ipv6 dhcpv6 trust
nx9500-6C8809(config-device-B4-C7-99-6D-CD-4B-if-ge1)#

Related Commands

no Removes or reverts IPv6 settings on this interface