3Com Switch 8800 Configuration Guide
Chapter 37 BGP/MPLS VPN Configuration
37-50
[PE3] interface loopback 0
[PE3-LoopBack0] ip address 33.1.1.1 255.255.255.255
[PE3-LoopBack0] quit
Set up MP-IBGP adjacency between PE3 and PE1 to exchange inter-PE VPN routing
information and activate MP-IBGP peer in VPNv4 sub-address family view.
[PE3] bgp 100
[PE3-bgp] group 11
[PE3-bgp] peer 11.1.1.1 group 11
[PE3-bgp] peer 11.1.1.1 connect-interface loopback 0
[PE3-bgp] ipv4-family vpnv4
[PE3-bgp-af-vpn] peer 11 enable
[PE2-bgp-af-vpn] peer 11.1.1.1 group 11
[PE2-bgp-af-vpn] peer 11.1.1.1 allow-as-loop 1
[PE3-bgp-af-vpn] quit
[PE3-bgp] quit
37.4.5 CE Dual-home Configuration Example
I. Network requirements
For the applications which require high robustness of network, you may use CE
dual-home networking mode.
CE1 and CE2 are dual-homed; they are connected to both PE1 and PE2. Three PEs
are connected to each other so the links between them are backed up. CE3 and CE4
are single-homed; each of them is only connected to one PE.
CE1 and CE3 are in one VPN, and CE2 and CE4 are in another VPN. The two VPNs
cannot intercommunicate with each other.