Configuring an IPv6 link-local address
IPv6 link-local addresses can be configured in either of the following ways:
Automatic generation—The device automatically generates a link-local address for an interface according to the link-local address prefix (FE80::/10) and the link-layer address of the interface.
Manual assignment—IPv6 link-local addresses can be assigned manually.
An interface can have only one link-local address. To avoid link-local address conflicts, use the automatic generation method.
Manual assignment takes precedence over automatic generation.
If you first use automatic generation and then manual assignment, the manually assigned link-local address will overwrite the automatically generated one.
If you first use manual assignment and then automatic generation, the automatically generated link-local address will not take effect and the link-local address is still the manually assigned one. If you delete the manually assigned address, the automatically generated link-local address is validated.
To configure automatic generation of an IPv6 link-local address for an interface:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. Configure the interface to automatically generate an IPv6 link-local address. | ipv6 address auto link-local | Optional. By default, no link-local address is configured on an interface. After an IPv6 global unicast address is configured on the interface, a link-local address is generated automatically. |
To configure an IPv6 link-local address manually:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. Configure an IPv6 link-local address manually. | ipv6 address ipv6-address link-local | Optional. By default, no link-local address is configured on an interface. After an IPv6 global unicast address is configured on the interface, a link-local address is generated automatically. |
After an IPv6 global unicast address is configured for an interface, a link-local address is generated automatically.
The automatically generated link-local address is the same as the one generated by using the ipv6 address auto link-local command.
If a link-local address is manually assigned to an interface, this manual link-local address takes effect. If the manually assigned link-local address is removed, the automatically generated link-local address takes effect.
The undo ipv6 address auto link-local command can only remove the link-local addresses generated through the ipv6 address auto link-local command.
If an IPv6 global unicast address is already configured for an interface, the interface still has a link-local address because the system automatically generates one for the interface.
If no IPv6 global unicast address is configured, the interface has no link-local address.