R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Figure 180 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 below, Router A and Router B establish an eBGP
neighbor relationship, and Router B and Router C establish an iBGP neighbor relationship. They are on
the same broadcast network 1.1.1.0/24. When Router 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 next hop (1.1.1.2/24)
for routes sent to Router A by using the peer next-hop-local command as needed.
Figure 181 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.
Follow these steps to configure the next hop attribute:
To do… Use the command…
Remarks
Enter system view system-view
—
Enter BGP view bgp as-number
—
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.
Configuring the AS-PATH attribute
1. Permit local AS number to appear in routes from a peer/peer group
In general, BGP checks whether the AS_PATH attribute of a route from a peer contains the local AS
number. If so, it discards the route to avoid routing loops.
This task allows you to permit local AS number to appear in routes from a peer/peer group and specify
the appearance times.
To do… Use the command…
Remarks
Enter system view system-view
—
Enter BGP view bgp as-number
—