Configuring The As_Path Attribute - HPE 5800 Series Configuration Manual

Step
Specify the router as the
3.
next hop of routes sent to a
peer or peer group.
NOTE:
If you have configured BGP load balancing on a BGP router, the router will set 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.

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
Enter system view.
1.
Enter BGP view or
2.
BGP-VPN instance view.
Permit local AS number to
3.
appear in routes from a peer
or peer group and specify
the appearance times.
Disabling BGP from considering AS_PATH during best route selection
Step
Enter system view.
1.
Command
peer { group-name | ip-address }
next-hop-local
Command
system-view
•
Enter BGP view:
bgp as-number
•
Enter BGP-VPN instance
view:
a. bgp as-number
b. ipv4-family
vpn-instance
vpn-instance-name
peer { group-name | ip-address }
allow-as-loop [ number ]
Command
system-view
200
Remarks
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.
Remarks
N/A
Use either approach.
Optional.
By default, the local AS number is
not allowed to appear in routes
from a peer or peer group.
Remarks
N/A