Error: "Internal Server Error a different object with the same identifier value was already associated with the session" when performing a failover or migration

Products

• VMware Cloud Director
• VMware Live Recovery

Issue/Introduction

• Attempting to failover / migrate VM's using Flexible storage profile assignment that has multiple disks configured to vSAN and NFS storage policies. 
• Error in the VMware Cloud Director Availability UI:
  
  "Unexpected VMware Cloud Director Error: Internal Server Error a different object with the same identifier value was already associated with the session"  
  
  
• Error when performing failover.
• VMs that were experiencing the error had the Advanced Datastore Settings option enabled and different disk policies assigned.
• In the /opt/vmware/vcloud-director/logs/vcloud-container-debug.log for the destination VMware Cloud Director you see entries similar to:
  
  2025-09-30 16:21:45,918 | ERROR    | storage-fabric-activity-pool-1564 | ReconfigureStoredVmActivity    | [Activity Execution] Uncaught Exception during Activity execution. Recent phase: com.vmware.vcloud.fabric.storage.storedVm.impl.ReconfigureStoredVmActivity$UpdateDbPhase@2805be4 - Handle: urn:uuid:########-####-####-####-############, Current Phase: ReconfigureStoredVmActivity$UpdateDbPhase | requestId=UI-########-####-####-####-############-####-##-########-####-####-####-############,request=PUT https://vcloud.example.com/api/vApp/vm-########-####-####-####-############/networkConnectionSection,requestTime=1759249292197,remoteAddress=##.##.##.###:21251,userAgent=Apache-HttpClient/4.5.14 (Java/17.0.12),accept=application/*+xml;version 38.0 vcd=########-####-####-####-############,task=########-####-####-####-############ activity=(com.vmware.vcloud.backendbase.management.system.TaskActivity,urn:uuid:########-####-####-####-############) activity=(com.vmware.vcloud.fabric.storage.storedVm.impl.ReconfigureStoredVmActivity,urn:uuid:########-####-####-####-############) 
 java.util.concurrent.ExecutionException: org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.vmware.vcloud.common.model.storagefabric.VmDiskStorageClassModel#com.vmware.vcloud.common.model.storagefabric.VmDiskId@########] 
   at com.vmware.vcloud.activity.executors.ActivityRunner.run(ActivityRunner.java:136) 
   at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) 
   at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) 
   at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) 
   at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) 
   at java.base/java.lang.Thread.run(Thread.java:829) 
 Caused by: org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.vmware.vcloud.common.model.storagefabric.VmDiskStorageClassModel#com.vmware.vcloud.common.model.storagefabric.VmDiskId@########] 
   at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:191) 
   at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:144) 
   at org.hibernate.event.def.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:154) 
   at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:110) 
   at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:636) 
   at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:628) 

Environment

• VMware Cloud Director 10.6.X
• VMware Cloud Director Availability 4.7.X

Cause

This issue occurs due to how RT-VMs are reconfigured during a migration and failover.

Resolution

Broadcom Engineering is aware of this issue and are actively working to fix this in a future release of VMware Cloud Director.

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Workaround

Please ensure that the Flexible storage profile assignment has multiple disk storage policies that use the same storage type.