3Com 10014299 manual Configuring a Static Route, Transmitting interface or next hop address

410CHAPTER 27: CONFIGURING STATIC ROUTES

Default routes are very useful in network. In a typical network with hundreds of routers, dynamic routing protocols may consume lots of bandwidth resource. Using default route means that you can replace high bandwidth links with adequate bandwidth links to meet the requirements of communication for a large number of subscribers.

Configuring a Static Route

Configuring a Static Route

Configuring static and default routes involves tasks described in the following sections:

■Configuring a Static Route

■Configuring a Default Route

Perform the following configurations in system view.

Table 466 Configure a Static Route

Operation	Command
Configure a static route	ip route-static ip-address { mask mask-length }
	{ interface-type interface-number
	nexthop-address } [ preference value ] [ reject
	blackhole ]
Delete a static route	undo ip route-static { all ip-address { mask
	mask-length } [ interface-type interface-number
	nexthop-address ] [ preference value ] }

The explanation of each parameter is as follows:

■IP address and network mask

IP address is shown in dotted decimal format. The 1s in the 32 bit mask must be continuous. The mask can also be presented in the dotted decimal format or by the mask length, that is, the number of “1”s in the mask.

■Transmitting interface or next hop address

In the configuration of static routes, the transmitting interface interface-type interface-number or the next hop address nexthop-address can be designated as required by the actual conditions.

You can specify the transmitting interfaces in the following cases:

■For interfaces that support resolution from the network address to the link layer address (like Ethernet interface supporting ARP), if a host address has been specified for Ip-addressand mask (or mask-length), and if the destination address is in a network directly connected to this interface, then you can specify the transmitting interface.

■For a point-to-point type interface, specifying the transmitting interface implies specifying the address of next hop. In this case the address of the remote interface is considered the address of next hop. If the serial interface is encapsulated with the PPP protocol, the IP address of the node on other end can be determined through PPP consultation. Then you only need to specify the transmitting interface instead of the address of next hop.

When NBMA interfaces like the interface encapsulated with X.25 or frame relay or dial-up interface support point-to-multipoint mode, besides configuring the IP route, you must also set up the secondary route at the link layer and map from the