Label information used by a downstream LSR is mirrored on an upstream LSR.
In particular, a copy of the label information database in the downstream
LSR from LDP sessions is stored on the upstream LSR. The label
information database and corresponding mirror are synchronized. The
mirror is employed to facilitate recovery from control plane failure
through comparison of the label information database with the mirror. For
example, the intersection of the label information database and the
mirror may be calculated and employed as the updated label information
database and mirror.