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TATIC

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ONFIGURATION

this packet will be discarded, and an internet control message protocol (ICMP) 
packet will be sent to the originating host to inform that the destination host or 
network is unreachable.

Static Route Configuration includes:

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■

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Perform the following configurations in system view.

The parameters are explained as follows:

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IP address and mask

The IP address and mask are in a dotted decimal format. As "1"s in the 32-bit 
mask is required to be consecutive, the dotted decimal mask can also be replaced 
by the mask-length (which refers to the digits of the consecutive "1"s in the 
mask).

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Next hop address and NULL interface

When configuring a static route, you can specify the gateway-address to decide 
the next hop address, depending on the actual conditions.

In fact, for all the routing entries, the next hop address must be specified. When IP 
layer transmits an IP packet, it will first search the matching route in the routing 
table according to the destination address of the packet. Only when the next hop 
address of the route is specified can the link layer find the corresponding link layer 
address, and then forward the packet according to this address.

The packets sent to NULL interface, a kind of virtual interface, will be discarded at 
once. This can decrease the system load.

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Preference

Depending on the configuration of preference, you can achieve different route 
management policies. For example, to implement load sharing, you can specify 
the same preference for multiple routes to the same destination network. To 
implement route backup, you can specify different preferences for them.

Table 249   Configure a static route

Add a static route 

ip route-static [ vpn-instance vpn-instance-name-list ] ip-address { 
mask | mask-length } { interface-type interface-number | [ 
vpn-instance vpn-instance-name ] gateway-address } [ preference 
preference-value ] [ reject | blackhole ] 

Delete a static route 

undo ip route-static [ vpn-instance vpn-instance-name-list ] 
ip-address { mask | mask-length } { interface-type interface-number | 
[ vpn-instance vpn-instance-name ] gateway-address } [ 
preference preference-value ] [ reject | blackhole ]