R3102-R3103-HP 6600/HSR6600 Routers Layer 3 - IP Routing Configuration Guide

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IMPORTANT:
If you have configured BGP load balancing, the router sets itself as the next hop for routes sent to an IBGP
peer or peer group regardless of whether the peer next-hop-local command is configured.
To configure the NEXT_HOP attribute:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view or BGP-VPN
instance view.
• Enter BGP view:
bgp as-number
• Enter BGP-VPN instance view:
a. bgp as-number
b. ipv4-family vpn-instance
vpn-instance-name
Use either method.
3. Specify the router as the next
hop of routes sent to a peer or
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 or peer group, but does not
set it as the next hop for routes sent
to an IBGP peer or peer group.
Configuring the AS_PATH attribute
Permitting local AS number to appear in routes from a peer or 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.
However, in certain network environments (a Hub&Spoke network in MPLS L3VPN, for example), the
AS_PATH attribute of a route from a peer must be allowed to contain the local AS number; otherwise, the
route cannot be advertised correctly.
To permit local AS number to appear in routes from a peer or peer group and specify the appearance
times.
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view or BGP-VPN
instance view.
• Enter BGP view:
bgp as-number
• Enter BGP-VPN instance view:
a. bgp as-number
b. ipv4-family vpn-instance
vpn-instance-name
Use either method.
3. Permit local AS number to
appear in routes from a peer
or peer group and specify the
appearance times.
peer { group-name | ip-address }
allow-as-loop [ number ]
Optional.
By default, the local AS number is
not allowed to appear in routes
from a peer or peer group.