Configuring an IPv6 static neighbor address

You can use static IPv6 neighbors to manually specify the link-layer address for a given IPv6 endpoint.

About this task

Under normal operation you do not need to configure static IPv6 neighbors.

However, IPv6 static neighbors can be used to:

avoid the overhead associated with dynamic neighbor discovery protocol traffic
help troubleshoot specific network scenarios

Note

IPv6 static neighbors are not supported on SMLT.
When you add or remove IPv6 static neighbors that point to a nexthop router, make sure that you have disabled the IPv6 interface.

Not all parameters are available in non-default VRFs.

Procedure

Enter either Global Configuration mode or VRF Router Configuration mode for a specific VRF context:

enable

configure terminal

Optional: router vrf WORD<1-16>
Configure an IPv6 neighbor address:

ipv6 neighbor WORD<0-128> port {slot/port[sub-port]} mac <0x00:0x00:0x00:0x00:0x00:0x00> [vlan <1-4059>
Configure optional parameters if the default values do not meet your requirements:
1. Configure the hop limit:
  
  ipv6 hop-limit <0–255>
  
  The default is 64.
2. Configure ICMP network address unreachable messages:
  
  ipv6 icmp addr-unreach
3. Configure the ICMP error interval:
  
  ipv6 icmp error-interval <1–2147483647>
  
  The interval is in milliseconds. An interval of 0 results in no error messages. The default is 1000.
4. Configure the ICMP error quota:
  
  ipv6 icmp error-quota <0-2000000>
  
  The default is 50.
5. Configure ICMP port unreachable messages:
  
  ipv6 icmp port-unreach
6. Enable response to icmp echo multicast packets:
  
  ipv6 icmp echo-multicast-request
  
  The default is disabled.
7. Enable ICMP network unreachable messages:
  
  ipv6 icmp unreach-msg
  
  The default is disabled.

Example

Add an IPv6 neighbor for a brouter port:

Switch:1(config)#ipv6 neighbor 3000:0:0:0:0:0:0:2 port 1/11 mac 00:0c:42:07:35:90

Add an IPv6 neighbor for a VLAN:

Switch:1(config)#ipv6 neighbor 3000::3 port 1/12 mac 01:02:03:04:05:06 vlan 20

Variable definitions

Use the data in the following table to use the ipv6 commands in this procedure.


Variable	Value
forwarding	Configures whether this entity is an IPv6 router with respect to the forwarding of datagrams received by, but not addressed to, this entity. Enable forwarding to act as a router. The default is enabled.
hop-limit `<0–255>`	Configures the hop limit. The default is 64.
icmp addr-unreach	Enables ICMP address unreachable messages. The default is enabled.
icmp echo-multicast-request	Enable response to icmp echo multicast packets. The default is enable.
icmp error interval `<1–2147483647>`	Configures the interval (in milliseconds) for sending ICMPv6 error messages. The default is 1000.
icmp error-quota `<0-2000000>`	Configures the number of ICMP error messages that can be sent during the ICMP error interval. A value of zero instructs the system not to send an ICMP error messages. The default value is 50.
icmp port-unreach	Enables ICMP port unreachable messages. The default is enabled.
icmp unreach-msg	Enables ICMP network unreachable messages. The default is disabled.
neighbor `WORD<0-128>` port {slot/port[sub-port]} mac <0x00:0x00:0x00:0x00:0x00:0x00> [vlan `<1-4059>` ]	Creates a static IPv6 neighbor with the following variables: `WORD<0-128>` specifies the IPv6 addressof the neighbor in hexadecimal colon format. `{slot/port[/sub-port]}` specifies the brouter port to use for the neighbor. Identifies a single slot and port. If the platform supports channelization and the port is channelized, you must also specify the sub-port in the format slot/port/sub-port. mac <0x00:0x00:0x00:0x00:0x00:0x00> specifies the MAC address of the neighbor. vlan `<1-4059>` specifies the VLAN ID to use for the neighbor. Specifies the VLAN ID in the range of 1 to 4059. By default, VLAN IDs 1 to 4059 are configurable and the system reserves VLAN IDs 4060 to 4094 for internal use. On switches that support the vrf-scaling and spbm-config-mode boot configuration flags, if you enable these flags, the system also reserves VLAN IDs 3500 to 3998. VLAN ID 1 is the default VLAN and you cannot create or delete VLAN ID 1. Static IPv6 neighbors do not maintain any state machine and the system assumes that they are always reachable.