HP 12500 Series Configuration Manual page 229

Configuring eBGP between PE and CE
Configure the PE
1.
To configure the PE:
To do...
Enter system view
Enable BGP and enter BGP view
Enter BGP VPN instance view
Configure the CE as the VPN eBGP
peer
Redistribute the routes of the local
CEs
Configure BGP to filter routes to be
advertised
Configure BGP to filter received
routes
Allow the local AS number to
appear in the AS_PATH attribute of
a received route and set the
maximum number of repetitions
NOTE:
Normally, BGP detects routing loops by AS number. In the hub and spoke network scheme, however, with
eBGP running between PE and CE, the routing information the PE advertises to a CE carries the number of
the AS where the PE resides. Therefore, the route updates that the PE receives from the CE also include the
number of the AS where the PE resides. This causes the PE unable to receive the route updates. In this case,
routing loops must be allowed.
Configure the CE
2.
To configure the CE:
To do...
Enter system view
Enter BGP view
Configure the PE as the eBGP peer
Configure the route redistribution
and advertisement behavior
Use the command...
system-view
bgp as-number
ipv4-family vpn-instance
vpn-instance-name
peer { group-name | ip-address }
as-number as-number
import-route protocol [ process-id ]
[ med med-value | route-policy
route-policy-name ] *
filter-policy { acl-number |
ip-prefix ip-prefix-name } export
[ direct | isis process-id | ospf
process-id | rip process-id | static ]
filter-policy { acl-number |
ip-prefix ip-prefix-name } import
peer { group-name | ip-address }
allow-as-loop [ number ]
Use the command...
system-view
bgp as-number
peer { group-name | ip-address }
as-number as-number
import-route protocol [ process-id ]
[ med med-value | route-policy
route-policy-name ] *
221
Remarks
—
—
Required
Required
Required
A PE must redistribute the routes of
the local CEs into its VPN routing
table so it can advertise them to the
peer PE.
Optional
By default, BGP does not filter
routes to be advertised.
Optional
By default, BGP does not filter
received routes.
Optional
For the hub and spoke network
scheme
Remarks
—
—
Required
Optional
A CE must advertise its routes to the
connected PE so the PE can
advertise them to the peer CE.