H3C Technologies H3C WX3000E Series Wireless Switches - Manual (Page 21)

11
Step Command Remarks
3. Set the interface description. description text
Optional.
By default, the description of a
loopback interface is interface name
Interface.
4. Shut down the loopback
interface.
shutdown
Optional.
By default, a loopback interface is up.
5. Restore the default settings. default Optional.
You can configure settings such as IP addresses and IP routes on loopback interfaces. For more
information, see Layer 3 Configuration Guide.
Configuring the null interface
Overview
A null interface is a completely software-based logical interface, and is always up. However, you cannot
use it to forward data packets or configure an IP address or link layer protocol on it. With a null interface
specified as the next hop of a static route to a specific network segment, any packets routed to the
network segment are dropped. The null interface provides a simpler way to filter packets than ACL. You
can filter uninteresting traffic by transmitting it to a null interface instead of applying an ACL.
For example, by executing the ip route-static 92.101.0.0 255.255.0.0 null 0 command (which configures
a static route leading to null interface 0), you can have all the packets destined to the network segment
92.101.0.0/16 discarded.
Only one null interface, interface Null 0, is supported on your device. You cannot remove or create a null
interface.
Configuration procedure
To enter null interface view:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter null interface
view.
interface null 0
The Null 0 interface is the default null interface
on your device. It cannot be manually created
or removed.
3. Set the interface
description.
description text
Optional.
By default, the description of a null interface is
interface name Interface.
4. Restore the default
settings.
default Optional.