This document specifies an extension to MPLS Operation, administration, and Maintenance (OAM) to operate an MPLS Transport Profile (MPLS-TP) Label Switched Path (LSP), bi-directional RSVP-TE tunnels, pseudowires (PW), or Multi-segment PWs in loopback mode for management purpose. This extension includes mechanism to lock and unlock MPLS-TP Tunnels (i.e. data and control traffic) and can be used to loop all traffic (i.e, data and control traffic) at a specified LSR on the path of the MPLS-TP LSP back to the source.