Configuring a null interface
A null interface is a virtual interface and is always up, but you cannot use it to forward data packets or configure it with an IP address or link layer protocol. The null interface provides a simpler way to filter packets than ACL. You can filter undesired traffic by transmitting it to a null interface instead of applying an ACL. For example, if you specify a null interface as the next hop of a static route to a network segment, any packets routed to the network segment are dropped.
To configure a null interface:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter null interface view. | interface null 0 | Interface Null 0 is the default null interface on the device and cannot be manually created or removed. Only one null interface, Null 0, is supported on the device. The null interface number is always 0. |
3. Set the interface description. | description text | The default setting is NULL0 Interface. |
4. Restore the default settings for the null interface. | default | N/A |