Configuring Link-local Addresses for Interfaces
Context
Link-local addresses are used in neighbor discovery or stateless autoconfiguration. An IPv6 link-local address is generated by either of the following methods:
- Generated automatically: A device automatically generates a link-local address for an interface based on the link-local prefix (FE80::/10) and link layer address of the interface.
- Configured manually: You can manually configure an IPv6 link-local address for an interface.
Each interface can be configured with only one link-local address. To prevent link-local address conflict, automatically generated link-local addresses are recommended. After an interface is configured with an IPv6 global unicast address, it automatically generates a link-local address.
Manually configured link-local addresses have a higher priority than automatically generated ones. Manually configured addresses can overwrite automatically generated ones, but automatically generated addresses cannot overwrite manually configured ones. If manually configured addresses are deleted, the automatically generated ones that were previously overwritten take effect again.
Procedure
- Run system-view
The system view is displayed.
- Run ipv6
IPv6 packet forwarding is enabled.
By default, IPv6 packet forwarding is disabled.
- Run interface interface-type interface-number
The specified interface view is displayed.
- (Optional) On an Ethernet interface, run undo portswitch
The interface is switched to Layer 3 mode.
By default, an Ethernet interface works in Layer 2 mode.
Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support switching between Layer 2 and Layer 3 modes.
- Run ipv6 enable
The IPv6 function is enabled on the interface.
By default, the IPv6 function is disabled on an interface.
- Run either of the following commands to configure a link-local address for an interface:
Run ipv6 address ipv6-address link-local
A link-local address is configured for an interface.
Run ipv6 address auto link-local
A link-local address is automatically generated.