3com S7906E Manuel De Montage

 

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Create a Loopback interface 
and enter Loopback interface 
view 

interface loopback 
interface-number 

— 

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. 

Shut down the loopback 
interface 

Optional 

A loopback interface is up on 
being created. 

 

z 

The subnet mask of the IP address assigned to a Loopback interface can only be 32 bits in 

length. 

z 

Parameters such as IP addresses and IP routes can be configured on Loopback interfaces. Refer 

to the IP Services Volume for detailed configurations. 

 

A null interface is a completely software-based logical interface. A null interface is always up. However, 

you can neither use it to forward data packets nor 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 you a simpler way to 

filter packets than ACL. That is, 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. 

Currently, only one null interface, that is, Null 0 is supported on your device. You can neither remove 

this null interface nor create a new one.   

Follow these steps to enter null interface view: 

Enter system view 

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