Configuring an ospf sham link, Basic mpls l3vpn architecture, Mpls l3vpn concepts – H3C Technologies H3C S12500-X Series Switches User Manual

Page 144

Advertising
background image

133

Do not configure the peer default-route-advertise vpn-instance and peer upe route-policy commands at

the same time.
Do not connect an SPE to a CE directly. If an SPE must be directly connected to a CE, the VPN instance

on the SPE and that on the UPE must be configured with different RDs.
To configure HoVPN:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter BGP view.

bgp as-number N/A

3.

Specify a BGP peer or peer
group.

peer { group-name |
peer-address } as-number

as-number

By default, no BGP peer is
specified.

4.

Enter BGP-VPN VPNv4
address family view.

address-family vpnv4

N/A

5.

Enable BGP-VPNv4 route

exchange with the peer or
peer group.

peer { group-name | ip-address }
enable

By default, BGP does not exchange
VPNv4 routes with any peer.

6.

Specify the BGP peer or peer
group as a UPE.

peer { group-name | ip-address }
upe

By default, no peer is a UPE.

7.

Advertise routes to the UPE.

Advertise a default VPN route

to the UPE:
peer { group-name |

ip-address }

default-route-advertise
vpn-instance

vpn-instance-name

Advertise routes permitted by a

routing policy to the UPE:

peer { group-name |

ip-address } upe route-policy
route-policy-name export

Use either command.
By default, no route is advertised to
the UPE.
Do not configure both commands.
The peer default-route-advertise

vpn-instance command advertises
a default route using the local

address as the next hop to the UPE,

regardless of whether the default
route is present in the local routing

table. However, if the specified

peer is not a UPE, the command
does not advertise a default route.

Configuring an OSPF sham link

When a backdoor link exists between the two sites of a VPN, you can create a sham link between PEs

to forward VPN traffic through the sham link on the backbone rather than the backdoor link. A sham link

is considered an OSPF intra-area route.
The source and destination addresses of the sham link must be loopback interface addresses with 32-bit
masks. The loopback interfaces must be bound to VPN instances, and their addresses are advertised

through BGP.
Before you configure an OSPF sham link, complete the following tasks:

Configure basic MPLS L3VPN (OSPF is used between PE and CE).

Configure OSPF in the LAN where customer CEs reside.

Advertising