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 each PE.
Procedure
- Run system-view
The system view is displayed.
- Run bgp as-number
The BGP view is displayed.
- Run peer ipv4-address as-number as-number
The peer PE is configured as a BGP peer.
- Run peer ipv4-address connect-interface loopback interface-number
An interface is used to set up a TCP connection with the BGP peer.
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 recurse to tunnels. The route to the local loopback interface is advertised to the peer PE using an IGP on the MPLS backbone network.
- Run ipv4-family vpnv4
The BGP-VPNv4 address family view is displayed.
- (Optional) Run activate-route-tag
compatible
VPNv4 routes that carry a non-zero tag value are allowed to match the rule configured using the if-match tag
By default, the tag value of VPNv4 routes is 0, and the VPNv4 routes that carry tag 0 match the rule configured using the if-match tag command. If the tag carried in VPNv4 routes is not 0, the VPNv4 routes are not allowed to match the rule configured using the if-match tag command unless the activate-route-tag compatible command is run.
- Run peer ipv4-address enable
The ability to exchange VPNv4 routes with the BGP peer is enabled.
- Run commit
The configuration is committed.