H3C Technologies H3C SR8800 - Manual (Page 64)

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Step Command Remarks
3. Set a description for the
loopback interface.
description text
Optional.
By default, the description of an
interface is the interface name
followed by the “Interface” string.
4. Shut down the loopback
interface.
shutdown
Optional.
A loopback interface is up once
created.
5. Restore the default settings. default Optional.
CAUTION:
Parameters such as IP addresses can be configured on loopback interfaces. For more information, see
Layer 3—IP Services Configuration Guide.
Null interface
Introduction
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 for the network segment
92.101.0.0/16 discarded.
Currently, only one null interface, interface Null 0, is supported on your router. You cannot remove or
create a null interface.
Configuring interface Null 0
To configure interface Null 0:
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 a router. It can neither
be created nor removed.
3. Set a description for the null
interface.
description text
Optional.
By default, the description of an
interface is the interface name
followed by the “Interface” string.
4. Restore the default settings. default Optional.