To implement the QoS function on an MPLS network, the switch needs to determine the packet precedence according to the tunnel label on the MPLS public network. Therefore, it is necessary to map the tunnel label to the EXP field.
Before configuring the mapping of the precedence in the tunnel label, complete the following tasks:
Configure a local LDP session. For details, see Configuring Basic Functions of MPLS LDP.
Create a DiffServ domain. For details, see Priority Mapping Configuration (DiffServ Domain Mode) in the S2720, S5700, and S6700 V200R019C10 Configuration Guide - QoS.