Enabling IPv6 ND Strict Learning

This section describes how to enable IPv6 neighbor discovery (ND) strict learning to comply with RFC 4861.

Context

A device uses neighbor advertisement (NA) packets to establish neighbor entries, which does not comply with RFC 4861. To comply with RFC 4861, enable IPv6 ND strict learning. After you enable IPv6 ND strict learning on a device, the device uses NA packets only in response to neighbor solicitation (NS) packets to establish neighbor entries.

Procedure

Enable IPv6 ND strict learning globally.
1. Access the system view.
```
system-view
```
2. Enable IPv6 ND strict learning globally.
```
ipv6 nd learning strict
```
Enable IPv6 ND strict learning in the interface view.
1. Access the system view.
```
system-view
```
2. Access the interface view.
```
interface interface-type interface-number
```
  This command applies only to VLANIF interfaces, Eth-Trunk interfaces and Eth-trunk sub-interfaces.
3. Forcibly enable IPv6 ND strict learning on the interface.
```
ipv6 nd learning strict { force-disable | force-enable | trust }
```