Symptoms:
The administrator is facing this error in the replication "Operation Failed A runtime error occurred in the vSphere Replication Management Server. Exception details: 'Duplicate key host-#### (attempted merging values 30004.0 and 30004.0)'. Operation ID: #######-####-####-####-##########
vSphere Live Recovery 9.x
The error is caused by duplicate host entries in the vSphere Replication Server database. These duplicate entries conflict during the replication configuration process, leading to a runtime error.
Duplicate entries in the vrmsdb after an ESXi upgrade can happen due to issues with host re-registration, incomplete database updates, or synchronization errors between vCenter and vSphere Replication. These problems can result in the creation of duplicate host records.
NOTE: Below steps below must be performed on the target VR Appliance to remove the duplicate host-UUID. Take a snapshot of VR appliance before making the changes.
1) systemctl stop hms
2) Get VRMSDB password
cat /opt/vmware/hms/conf/embedded_db.cfg
3) cd /opt/vmware/vpostgres/current/bin/
4)./psql -U vrmsdb
5)Run the below command to get the hbrserverentity table details
SELECT vsrv_address, hostuuid, movalue, vsrv_sitename, hostid, connected from hbrserverentity;
6)To identify the active host UUID run the below
https://<target_vc>/mob/?moid=host-####&doPath=hardware.systemInfo
Replace #### with HostID found in the error
7) Use the HostUUID from the above output and compare it with all the host-UUID entries found for the same HostID in step 5.
8) Remove Host UUIDs that do not match.
Run the below command to remove the inactive host-UUID from the VR Database
DELETE from hbrserverentity where movalue = 'HBRSRV-################';
Find movalue from step 5
9) systemctl start hms
See the reference article for duplicate entry removal KB390498