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Syntax
interface loopback interface-number
undo interface loopback interface-number
Default
No loopback interfaces exist.
Views
System view
Predefined user roles
network-admin
Parameters
interface-number: Specifies a loopback interface by its number. The value range for this
argument is 0 to 127.
Usage guidelines
The physical layer state and link layer protocols of a loopback interface are always up unless the
loopback interface is manually shut down. You can use a loopback interface to achieve the following
purposes:
• Prevent the connection from being affected by the physical state of the interface.
• Improve the reliability of the connection.
For example, you can configure a loopback interface as the source interface for establishing an FTP
connection.
Examples
# Create Loopback 1.
<Sysname> system-view
[Sysname] interface loopback 1
[Sysname-LoopBack1]
interface null
Use interface null to enter null interface view.
Syntax
interface null 0
Default
A device has only one null interface (Null 0), which cannot be created or deleted.
Views
System view
Predefined user roles
network-admin
Parameters
0: Specifies Null 0. The null interface number is always 0.
Examples
# Enter Null 0 interface view.