User Manual

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Users Manual of XGS-6350-24X4C
via dynamic routing protocol.
Use the following command to shutdown or enable an interface in the interface configuration mode:
Command Description
shutdown Shuts down an interface.
no shutdown Enables an interface.
You can use the show interface command and the show running-config command to check whether an
interface has been shut down. An interface that has been shut down is displayed as ‘administratively down’ in
the show interface command display. For more details, please refer to the following example in ‘Interface
Shutdown Example’.
8.2.3 Configuring Logistical Interface
This section describes how to configure a logical interface. The contents are as follows:
 Configuring null interface
 Configuring loopback interface.
 Configuring aggregation interface
 Configuring VLAN interface
8.2.3.1 Configuring Null Interface
The whole system supports only one null interface. Its functions are similar to those of applied null devices on
most operating systems. The null interface is always available, but it never sends or receives communication
information. The interface configuration command no ip unreachable is the only one command available to
the null interface. The null interface provides an optional method to filtrate communication. That is, the
unwanted network communication can be routed to the null interface; the null interface can function as the
access control list.
You can run the following command in global configuration mode to specify the null interface:
Command Description
interface null0
Enters the null interface configuration
state.
The null interface can be applied in any command that takes the interface type as its parameter.
The following case shows how to configure a null interface for the routing of IP 192.168.20.0.
ip route 192.168.20.0 255.255.255.0 null 0
8.2.3.2 Configuring Loopback Interface
The loopback interface is a logistical interface. It always functions and continues BGP session even in the
case that the outward interface is shut down. The loopback interface can be used as the terminal address for
BGP session. If other switches try to reach the loopback interface, a dynamic routing protocol should be
configured to broadcast the routes with loopback interface address. Messages that are routed to the loopback