StorageGRID decommission job gets stuck against ADC node

• NetApp StorageGRID
• 11.6.x software release (pre-11.6.0.9)
• Nodes with ADC (Administrative Domain Controller) service running

• When decommission ADC nodes, job gets stuck and can not be resumed
• /var/local/log/decommission.d-rsm.log shows 500 Internal Server Error

DELETE to RSM service returned curl: (22) The requested URL returned error: 500 Internal Server Error500. Retrying in 10s

• When issuing curl http://localhost:8003/v1/raft/status command against all nodes in the same site, the results show different entries.

Example:

node1 displays 3 entries, but node2 shows 4.

   root@node1:~ $ curl  http://localhost:8003/v1/raft/status
    ...
     "clusterStatus": {
       "11286219": {
         "IPAddress": x.x.x.x:18003",
         "isLeader": false,
         "raftId": "ac36cb"
       },
       "11702624": {
         "IPAddress": "x.x.x.x:18003",
         "isLeader": true,
         "raftId": "b29160"
       },
       "11791281": {
         "IPAddress": "x.x.x.x:18003",
         "isLeader": false,
         "raftId": "b3ebb1"
       }
     },
     ...

   root@node2:~ # curl  http://localhost:8003/v1/raft/status
    ...
     "clusterStatus": {
       "11286219": {
         "IPAddress": "x.x.x.x:18003",
         "isLeader": false,    
         "raftId": "ac36cb"
       },
       "11702624": {
         "IPAddress": "x.x.x.x:18003",
         "isLeader": true,
         "raftId": "b29160"
       },
       "11791281": {
         "IPAddress": "x.x.x.x:18003",
         "isLeader": false,
         "raftId": "b3ebb1"
       },
       "11793293": {
         "IPAddress": "x.x.x.x:18003",
         "isLeader": false,
         "raftId": "b3f38d"
       }
     },
    ...