Displaying and Debugging the Routing Table 411
IP address to the link layer address (such as dialer route ip, x.25 map ip or
fr map ip commands, and so on). In this case, you cannot specify the
transmitting interface for the static route and must configure the IP address of the
next hop.
Actually, all the route items must mark the address of the next hop. According to
the destination address of packets, an IP router searches for the matching route in
the routing table. Only when the address of next hop is specified in the route, can
the link layer find a corresponding address through this address and transfer
packets.
However, in certain cases (such as PPP encapsulated in link layer), the address of
the node on the other end may be unknown when the router is configured so that
the sending interface has to be specified. In addition, if the sending interface has
been specified, it is not necessary to change the router's configuration when the
address of the node connected on the other end is changed
■Preference
Different preference configurations can achieve flexible route management. For
example, when configuring multiple routes to the same destination, if the
same preference is designated, load balancing can be realized. If different
preferences are designated, route standby can be realized.
■Other parameters
The reject and blackhole attributes refer to unreachable routes and black
hole routes respectively.
Configuring a Default
Route Perform the following configurations in system view.
Tabl e 467 Configure a Default Route
The parameters of this command mean the same as those in static route
configuration.
Displaying and Debugging the Routing Table
Tabl e 468 Displaying and Debugging the Routing Table
Operation Command
Configure a default
route ip route-static 0.0.0.0 { 0.0.0.0 | 0 } {
interface-type interface-number | nexthop-address
} [ preference value ] [ reject | blackhole ]
Delete a default route undo ip route-static 0.0.0.0 { 0.0.0.0 | 0 } [
interface-type interface-number | nexthop-address
] [ preference value ]
Operation Command
Display the abstract information of the
routing table display ip routing-table
Display the information of specific route display ip routing-table ip-address
Display the detailed information of the
routing table display ip routing-table verbose
Display the radix information of the
routing table display ip routing-table radix
Display the static routing table display ip routing-table static