H3C S9500 Series Operation Manual page 601

Operation Manual – BGP
H3C S9500 Series Routing Switches
Configure to send default route
to a peer group
Configure not to send default
route to a peer group
By default, a BGP speaker does not send default route to any peer group.
After you use the peer default-route-advertise command, the local router will send a
default route with the next hop as itself to the peer unconditionally, even if there is no
default route in BGP routing table.
IV. Configuring itself as the next hop when advertising routes
In general, when sending routes to the EBGP peer, the BGP speaker will set the next
hop address of the routing information as the local address. When sending routes to
the IBGP peer, the BGP speaker will not modify the next hop address.
In some networking conditions, when the routes are sent to the IBGP peer, you can
configure the local address of the sender as the next hop, consequently ensuring the
IBGP neighbors can find the correct next hop.
Perform the following configuration in BGP view.
Follow these steps to specify itself to be/not to be the next hop when advertising routes:
Configure itself as the next hop when
advertising routes
Disable the specification of itself as the
next hop when advertising routes
V. Removing private AS numbers while transmitting BGP update messages
Generally, the AS numbers (public AS numbers or private AS numbers) are included in
the AS paths while transmitting BGP update messages. This command is used to
configure certain outbound routers to ignore the private AS numbers while transmitting
update messages.
Perform the following configuration in BGP view to remove/include private AS numbers
while transmitting BGP update messages:
To do...
To do...
1-11
Use the command...
peer group-name default-route-advertise
undo peer group-name default-route-advertise
Use the command...
peer group-name next-hop-local
undo peer group-name next-hop-local
Chapter 1 BGP Configuration