R3721-F3210-F3171-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Configuring the next hop attribute
By default, when advertising routes to an IBGP peer/peer group, a BGP router does not set itself as the
next hop. However, to ensure a BGP peer can find the correct next hop in some cases, you need to
configure the router as the next hop for routes sent to the peer.
For example, as shown in Figure 282, R
ou
ter A and Router B establish an EBGP neighbor relationship,
and Router B and Router C establish an IBGP neighbor relationship. When Router B advertises a network
learned from Router A to Router C, if Router C has no route to IP address 1.1.1.1/24, you need to configure
Router B to set itself as the next hop (3.1.1.1/24) for the route to be sent to Router C.
Figure 282 Next hop attribute configuration
If a BGP router has two peers on a common broadcast network, it does not set itself as the next hop for
routes sent to an EBGP peer by default. As shown in Figure 283, Router
A and Router B establish an EBGP
neighbor relationship, and Router B and Router C establish an IBGP neighbor relationship. They are on
t h e s a m e b r o a d c a s t n e t w o r k 1.1.1. 0 / 24 . W h e n R o u t e r B sends EBGP routes to Router A, it does not set
itself as the next hop by default. However, you can configure Router B to set it as the nexthop (1.1.1.2/24)
for routes sent to Router A by using the peer next-hop-local command as needed.
Figure 283 Next hop attribute configuration
If you have configured BGP load balancing on a BGP router, the router will set it as the next hop for routes
sent to an IBGP peer/peer group regardless of whether the peer next-hop-local command is configured.
To configure the next hop attribute:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view.
bgp as-number N/A
3. Specify the router as the next
hop of routes sent to a
peer/peer group.
peer { group-name | ip-address }
next-hop-local
Optional.
By default, the router sets it as
the next hop for routes sent to
an EBGP peer/peer group,
but does not set it as the next
hop for routes sent to an IBGP
peer/peer group.