H3C Technologies H3C S12500-X Series Switches - Manual (Page 135)

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Step Command Remarks
4. Configure the CE as the VPN
EBGP peer.
peer { group-name |
ip-address } as-number
as-number
By default, no BGP peer is
configured.
For more information about BGP
peers and peer groups, see Layer
3—IP Routing Configuration
Guide.
5. Create and enter BGP VPN
IPv4 unicast family view.
address-family ipv4
[ unicast ]
N/A
6. Enable IPv4 unicast route
exchange with the specified
peer or peer group.
peer { group-name |
ip-address } enable
By default, BGP does not
exchange IPv4 unicast routes with
any peer.
7. Redistribute the routes of the
local CE.
import-route protocol
[ { process-id |
all-processes } [ med
med-value | route-policy
route-policy-name ] * ]
A PE must redistribute the routes of
the local CE into its VPN routing
table so it can advertise them to the
peer PE.
8. (Optional.) Allow the local AS
number to appear in the
AS_PATH attribute of a
received route, and set the
maximum number of
repetitions.
peer { group-name |
ip-address } allow-as-loop
[ number ]
By default, BGP discards incoming
route updates that contain the local
AS number.
BGP detects routing loops by
examining AS numbers. In a
hub-spoke network where EBGP is
running between a PE and a CE,
the routing information the PE
advertises to a CE carries the AS
number of the PE. Therefore, the
route updates that the PE receives
from the CE also include the AS
number of the PE. This causes the
PE to be unable to receive the route
updates. In this case, you must
configure this command to allow
routing loops.
2. Configure the CE:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter BGP view. bgp as-number N/A
3. Configure the PE as a BGP
peer.
peer { group-name | ip-address }
as-number as-number By default, no BGP peer is
created.
4. Create and enter BGP IPv4
unicast family view.
address-family ipv4 [ unicast ] N/A
5. Enable IPv4 unicast route
exchange with the specified
peer or peer group.
peer { group-name | ip-address }
enable
By default, BGP does not
exchange IPv4 unicast routes
with any peer.