Инструкции По Установке для 3com S7906E

 

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Enter BGP-VPNv4 subaddress 
family view 

Required 

Enable the exchange of 
BGP-VPNv4 routing 
information with a peer 

peer { group-name | 
ip-address } enable 

Required 

Specify a BGP peer or peer 
group as the UPE 

peer { group-name | 
ip-address } upe 

Required 

Specify to advertise default 
routes of a VPN instance to a 
UPE 

peer { group-name | 
ip-address } 
default-route-advertise 
vpn-instance 
vpn-instance-name 

Specify to advertise routes 
permitted by a specified routing 
policy to a UPE 

peer { group-name | 
ip-address } upe route-policy 
route-policy-name export 

Required 

Configure either command. 

By default, BGP does not 
advertise default routes to a 
VPNv4 peer. 

 

With the peer default-route-advertise vpn-instance command configured, the SPE always advertises 

a default route using the local address as the next hop address to the UPE, regardless of whether the 

default route is present in the local routing table or not. 

 

z 

The default routes of a VPN instance can be advertised to only a BGP peer or peer group that is 

UPE. 

z 

It is not recommended to configure the peer default-route-advertise vpn-instance command and 

the peer upe route-policy command at the same time. 

z 

It is not recommended for an SPE to be connected to a CE directly. If an SPE must be directly 

connected with a CE, the VPN instance on the SPE and that on the UPE must be configured with 

different RDs.

 

 

The sham link is considered an OSPF intra-area route.  It is used to ensure that the VPN traffic is 

transmitted over the backbone instead of the backdoor link between two CEs. 

The source and destination addresses of the sham link must be loopback interface addresses with 

32-bit masks. Besides, the loopback interfaces must be bound to the VPN instances and be advertised 

through BGP. 

Before configuring OSPF sham link, be sure to complete these tasks: 

z 

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

z 

Configuring OSPF in the LAN where CEs reside