3com S7906E 설치 설명서

 

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For inter-provider VPN option B, two configuration methods are available: 

z 

Do not change the next hop on an ASBR. With this method, you still need to configure MPLS LDP 

between ASBRs. 

z 

Change the next hop on an ASBR. With this method, MPLS LDP is not required between ASBRs. 

Currently, only the second method is supported. Therefore, MP-EBGP routes will get their next hops 

changed by default before being redistributed to MP-IBGP. On conventional BGP, however, EBGP 

routes to be advertised to IBGP do not have their next hops changed by default. If the next hops need to 

be changed to the local addresses, you can configure the peer  {  ip-address | group-name } 

next-hop-local command. For information about the command, refer to BGP Configuration in the IP 

Routing Volume. 

 

You need to establish ordinary IBGP peer relationship between PEs and ASBR PEs in an AS and 

MP-EBGP peer relationship between PEs of different ASs. 

The PEs and ASBR PEs in an AS must be able to exchange labeled IPv4 routes. 

Follow these steps to configure a PE for inter-provider VPN option C: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

— 

Configure the ASBR PE in the 
same AS as the IBGP peer 

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

Required 

Enable the PE to exchange 
labeled IPv4 routes with the 
ASBR PE in the same AS 

peer { group-name | 
ip-address } 
label-route-capability 

Required 

By default, the device does not 
advertise labeled routes to the 
IPv4 peer/peer group. 

Configure the PE of another AS 
as the EBGP peer 

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

Required 

Enter BGP-VPNv4 subaddress 
family view 

— 

Enable the PE to exchange 
BGP VPNv4 routing 
information with the peer 

peer { group-name | 
ip-address } enable 

Required 

Configure the PE not to change 
the next hop of a route when 
advertising it to the EBGP peer 

peer { group-name | 
ip-address } 
next-hop-invariable 

Optional 

Required only when RRs are 
used to advertise VPNv4 
routes, where the next hop of a 
route advertised between RRs 
cannot be changed.