Establishing MP-IBGP Peer Relationships Between PEs

MP-IBGP uses extended community attributes to advertise VPNv4 routes between PEs.

Context

If VPN sites in a basic BGP/MPLS IP VPN need to communicate, PEs must use MP-IBGP to advertise VPNv4 routes with the RD information to each other. Since all the PEs reside in the same AS, MP-IBGP peer relationships can be set up between them.

Perform the following steps on the PEs that are connected to CEs:

Procedure

Access the system view.
```
system-view
```
Access the BGP view.
```
bgp { as-number-plain | as-number-dot }
```

Configure the peer PE as a BGP peer.

peer ipv4-address as-number { as-number-plain | as-number-dot }

Use an interface to set up a TCP connection with the BGP peer.
```
peer ipv4-address connect-interface loopback interface-number
```
A PE must use a loopback interface address with a 32-bit mask to set up an MP-IBGP peer relationship with the peer PE so that VPN routes can be iterated to tunnels. The route to the local loopback interface is advertised to the peer PE using an IGP on the MPLS backbone network.
Access the BGP-VPNv4 address family view.
```
ipv4-family vpnv4
```
Enable the device to exchange VPN IPv4 routes with the BGP peer.
```
peer ipv4-address enable
```