D-Link DI-1750 Reference Manual page 258

6.12.15 Disable Next-Hop Processing on BGP Updates
You can configure the router to disable next-hop processing for BGP updates to a neighbor. This might
be useful in nonmeshed networks such as Frame Relay or X.25, where BGP neighbors might not have
direct access to all other neighbors on the same IP subnet. There are two ways to disable next-hop
processing:
Provide a BGP connecting local IP address to instead the next-hop addres of outbound routes;
Use a route map to specify that the next-hop address of the inbound routes or the outbound routes
(refer to other chapters)
To disable next-hop processing and provide a specific address to be used instead of the next-hop
address, use the following command in router configuration mode:
neighbor
next-hop-self
input neighbor Command，prompt is as below:
(00)A.B.C.D
Please Input the code of command to be excute(0-0): 0
input 0，Select A.B.C.D option ，then promptis as below：
Please input a IP Address:
input IP ，prompt is as below:
(00)default-originate
......
(06)next-hop-self
......
Please Input the code of command to be excute(0-17): 6
input 6，Select next-hop-self option .
Configuring this command causes the current router to advertise itself as the next hop for the specified
neighbor. Therefore, other BGP neighbors will forward to it packets for that address. This is useful in a
nonmeshed environment, since you know that a path exists from the present router to that address. In a
network broadcast ing environment, this is not useful, since it will result in unnecessary extra hops.
6.12.16 Configure Advanced BGP Features
The tasks in this section are for configuring advanced BGP features.
1. Use Route Maps to Filter and Modify Route Updates
You can use a route map on a per-neighbor basis to filter updates and modify various attributes. A route
map can be applied to either inbound or outbound updates. Only the routes that pass the route map are
sent or accepted in updates.
On both the inbound and the outbound updates, we support matching based on autonomous system
path, community, and network numbers. Autonomous system path matching requires the aspath-list
command, community based matching requires the community-list command and network-based
matching requires the ip access-list command.
Use the following BGP configuring command to configure the route update, which is modified and
filtered by route map:
neighbor{ip-address|peer-group-name}
config-route-map-name {in | out}
In the prompt Select 12 option ，prompt is as below:
(00)A.B.C.D
Command
{ip-address |
peer-group-name}
IP address of neighbor
Permit announcement of default route to neighbor
Set nexthop value to self
Command
IP address of neighbor
Model Name
disable next-hop processing of BGP
neighbor update
Apply a route map to inbound or outbound
route-map
routes.
- 256 -
Purpose
Purpose