Configuring Route Advertisement Between Pes - 3Com S7906E Configuration Manual

Normally, BGP detects routing loops by AS number. In the hub and spoke networking 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.
2) On a CE
Follow these steps to configure EBGP between PE and CE on a CE:
To do...
Enter system view
Enter BGP view
Configure the PE as the peer
Configure the route
advertisement behavior
Exchange of BGP routes for a VPN instance is the same as that of ordinary BGP routes.
The configuration task in BGP instance view is the same as that in BGP view. For detailed
information, refer to BGP Configuration and BGP Commands in the IP Routing Volume.
For information about BGP peer and peer group configuration, refer to BGP Configuration and
BGP Commands in the IP Routing Volume. This chapter does not differentiate between peer and
peer group.

Configuring Route Advertisement Between PEs

Follow these steps to configure route advertisement between PEs:
To do...
Enter system view
Enter BGP view
Configure the remote PE as the
peer
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 ] *
Use the command...
system-view
bgp as-number
peer { group-name |
ip-address } as-number
as-number
1-31
Remarks
—
—
Required
Optional
A CE needs to advertise its
routes to the connected PE so
that the PE can advertise them
to the peer CE.
Remarks
—
Required
Required