MPLS - BGP customer prefixes do not appear in the LFIB

When implementing MPLS with BGP, and when using BGP as the routing protocol between the CE and the PE, the customer prefixes do not appear in the label switched information base (LFIB). In other words, customer prefixes are not labelled by LDP.

This behavior is by design.

LDP labels are used to denote specific paths within the MPLS core, so you will only see prefixes from within the core in the LFIB. The labels that exist within the LFIB are those of the next hop IP rather than the actual destination network prefix.

A PE receives a packet from a CE, and if the destination is a remote site reachable via another PE router, the BGP table for that VRF will have an entry indicating the next hop (which is typically the other PE router). The corresponding label is added to the packet.