For years, Cisco IOS® Software has supported the coexistence of dual command-line interfaces (CLIs) to configure quality of service (QoS) on its platforms:
• MQC (Modular QoS CLI) is by far the most adopted CLI by the vast majority of users, as it offers advanced capabilities such as configuration of traffic policing at three levels of policy map hierarchies.
• The legacy CLI offers only a reduced set of the functionalities that MQC offers, and Cisco has always maintained both CLIs at parity to allow early users to seamlessly upgrade their Cisco IOS Software.
Because of the low usage of the legacy CLI, and given that MQC is recognized as the most complete CLI for configuration of QoS on its equipment, Cisco has reached the decision to deprecate the legacy CLI for QoS.
In order to ease the transition for the few customers who need to, the deprecation plan will include two phases:
• Phase 1: The legacy commands will still be accessible and supported. However Cisco will no longer document them and a CLI warning message will be prompted to the user.
• Phase 2: The legacy commands will be deprecated. Error messages indicating unrecognized CLI commands will be prompted to the user.
Release notes and Cisco IOS Software documentation will provide details of the deprecated commands and their MQC equivalents.
The legacy commands will be permanently deprecated starting in phase 2, and this removal will propagate to various release trains with different timelines as given in Table 1.