After upgrading to 23.4R2-S3, the EVO does not allow to configure multiple MEPs under same MA.

root@acx7024-router1# commit
Dec 03 00:34:28
[edit protocols oam ethernet connectivity-fault-management maintenance-domain md-mx-pe]
'maintenance-association ma-mx-pe-up-down'
Multiple mep in ma not supported for this platform
error: configuration check-out failed

This configuration worked on 23.4R1, and I do not see in the release notes multiple MEP is not supported from 23.4R2.

root@acx7024-router1> show configuration protocols oam

Dec 03 07:42:26

ethernet {

  connectivity-fault-management {

    action-profile cfm-action-laser-off {

      event {

        interface-status-tlv [ down lower-layer-down ];

        adjacency-loss;

      }

      action {

        asynchronous-notification;

      }

    }

    maintenance-domain md-mx-pe {

      level 2;

      maintenance-association ma-mx-pe-up-down {

        continuity-check {

          interval 1s;

          loss-threshold 3;

          hold-interval 1;

          interface-status-tlv;

        }

      }

      maintenance-association ma-mx-pe-up-down-120 {

        continuity-check {

          interval 1s;

          loss-threshold 3;

          hold-interval 1;

          interface-status-tlv;

        }

        mep 120 {

          interface et-0/0/12.0;

          direction up;

          auto-discovery;

          remote-mep 121 {

            action-profile cfm-action-laser-off;

          }

        }

      }

      maintenance-association ma-mx-pe-up-down-130 {

        continuity-check {

          interval 1s;

          loss-threshold 3;

          hold-interval 1;

          interface-status-tlv;

        }

        mep 130 {

          interface et-0/0/13.0;

          direction up;

          auto-discovery;

          remote-mep 131 {

            action-profile cfm-action-laser-off;

          }

        }

      }

      maintenance-association ma-mx-pe-up-down-140 {

        continuity-check {

          interval 1s;

          loss-threshold 3;

          hold-interval 1;

          interface-status-tlv;

        }

        mep 140 {

          interface et-0/0/14.0;

          direction up;

          auto-discovery;

          remote-mep 141 {

            action-profile cfm-action-laser-off;

          }

        }

      }

Upon checking the release notes this restriction has been recently added due to below PR

The problem reported was EVO-PFEMAND process crash and not coming up again, Upon investigating it was found due to the unsupported configuration of using multiple MEPs under single MA and this was not fully qualified yet during internal testing.

Hence engineering has added a check while performing the configuration of using multiple MEP under single MD to throw a commit error.

https://www.juniper.net/documentation/us/en/software/junos/release-notes/23.4/junos-evo-release-notes-23.4r2/junos-evo-release-notes-23.4r2.pdf

Please refer Page No - 11.

**********************************************************************************************************************

CFM configuration with multiple MEP under same maintenance-association causes evo-pfemand process crash and CFM session might not come up. PR1786395

**********************************************************************************************************************

PR link:

PR1786395 - CFM configuration with multiple MEP under same maintenance-association cause evo-pfemand process crash and CFM session may not come up

https://prsearch.juniper.net/problemreport/PR1786395

Issue reported in - 23.4R1-EVO

Issue resolved in - evo:23.4R1-S1-EVO evo:23.4R2-EVO evo:24.1R1-EVO evo:24.2R1-EVO

Root cause - multiple up meps are configured under same MA and MD. This is not qualified yet.

Detectability-Info - Commit or image validation upgrade will fail.

Restoration-Steps - Change configuration to have unique MA names for each MEP