Merge "One SchemaSet per moduleSetTag"

13 files changed, 239 insertions, 430 deletions

diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationService.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationService.java
index fc215c9c01..e7fd247a08 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationService.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationService.java
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2021-2024 Nordix Foundation
+ *  Copyright (C) 2021-2025 Nordix Foundation
  *  Modifications Copyright (C) 2021 Pantheon.tech
  *  Modifications Copyright (C) 2021-2022 Bell Canada
  *  Modifications Copyright (C) 2023 TechMahindra Ltd.
@@ -138,17 +138,20 @@ public class CmHandleRegistrationService {
 
     protected void processRemovedCmHandles(final DmiPluginRegistration dmiPluginRegistration,
                                            final DmiPluginRegistrationResponse dmiPluginRegistrationResponse) {
-        final List<String> tobeRemovedCmHandleIds = dmiPluginRegistration.getRemovedCmHandles();
+        final List<String> toBeRemovedCmHandleIds = dmiPluginRegistration.getRemovedCmHandles();
+        if (toBeRemovedCmHandleIds.isEmpty()) {
+            return;
+        }
         final List<CmHandleRegistrationResponse> cmHandleRegistrationResponses =
-            new ArrayList<>(tobeRemovedCmHandleIds.size());
+            new ArrayList<>(toBeRemovedCmHandleIds.size());
         final Collection<YangModelCmHandle> yangModelCmHandles =
-            inventoryPersistence.getYangModelCmHandles(tobeRemovedCmHandleIds);
+            inventoryPersistence.getYangModelCmHandles(toBeRemovedCmHandleIds);
         updateCmHandleStateBatch(yangModelCmHandles, CmHandleState.DELETING);
 
         final Set<String> notDeletedCmHandles = new HashSet<>();
-        for (final List<String> tobeRemovedCmHandleBatch : Lists.partition(tobeRemovedCmHandleIds, DELETE_BATCH_SIZE)) {
+        for (final List<String> tobeRemovedCmHandleBatch : Lists.partition(toBeRemovedCmHandleIds, DELETE_BATCH_SIZE)) {
             try {
-                batchDeleteCmHandlesFromDbAndCaches(tobeRemovedCmHandleBatch);
+                deleteCmHandlesFromDbAndCaches(tobeRemovedCmHandleBatch);
                 tobeRemovedCmHandleBatch.forEach(cmHandleId ->
                     cmHandleRegistrationResponses.add(CmHandleRegistrationResponse.createSuccessResponse(cmHandleId)));
 
@@ -201,8 +204,9 @@ public class CmHandleRegistrationService {
 
     protected void processUpdatedCmHandles(final DmiPluginRegistration dmiPluginRegistration,
                                            final DmiPluginRegistrationResponse dmiPluginRegistrationResponse) {
-        dmiPluginRegistrationResponse.setUpdatedCmHandles(cmHandleRegistrationServicePropertyHandler
-            .updateCmHandleProperties(dmiPluginRegistration.getUpdatedCmHandles()));
+        final List<CmHandleRegistrationResponse> updatedCmHandles = cmHandleRegistrationServicePropertyHandler
+            .updateCmHandleProperties(dmiPluginRegistration.getUpdatedCmHandles());
+        dmiPluginRegistrationResponse.setUpdatedCmHandles(updatedCmHandles);
     }
 
     protected void processUpgradedCmHandles(
@@ -275,7 +279,7 @@ public class CmHandleRegistrationService {
 
     private CmHandleRegistrationResponse deleteCmHandleAndGetCmHandleRegistrationResponse(final String cmHandleId) {
         try {
-            deleteCmHandleFromDbAndCaches(cmHandleId);
+            deleteCmHandlesFromDbAndCaches(Collections.singletonList(cmHandleId));
             return CmHandleRegistrationResponse.createSuccessResponse(cmHandleId);
         } catch (final DataNodeNotFoundException dataNodeNotFoundException) {
             log.error("Unable to find dataNode for cmHandleId : {} , caused by : {}",
@@ -298,16 +302,9 @@ public class CmHandleRegistrationService {
         lcmEventsCmHandleStateHandler.updateCmHandleStateBatch(cmHandleStatePerCmHandle);
     }
 
-    private void deleteCmHandleFromDbAndCaches(final String cmHandleId) {
-        inventoryPersistence.deleteSchemaSetWithCascade(cmHandleId);
-        inventoryPersistence.deleteDataNode(NCMP_DMI_REGISTRY_PARENT + "/cm-handles[@id='" + cmHandleId + "']");
-        trustLevelManager.removeCmHandles(Collections.singleton(cmHandleId));
-        removeDeletedCmHandleFromModuleSyncMap(cmHandleId);
-    }
-
-    private void batchDeleteCmHandlesFromDbAndCaches(final Collection<String> cmHandleIds) {
-        inventoryPersistence.deleteSchemaSetsWithCascade(cmHandleIds);
+    private void deleteCmHandlesFromDbAndCaches(final Collection<String> cmHandleIds) {
         inventoryPersistence.deleteDataNodes(mapCmHandleIdsToXpaths(cmHandleIds));
+        inventoryPersistence.deleteAnchors(cmHandleIds);
         trustLevelManager.removeCmHandles(cmHandleIds);
         cmHandleIds.forEach(this::removeDeletedCmHandleFromModuleSyncMap);
     }
@@ -326,8 +323,11 @@ public class CmHandleRegistrationService {
 
     private List<CmHandleRegistrationResponse> upgradeCmHandles(final Map<YangModelCmHandle, CmHandleState>
                                                                     cmHandleStatePerCmHandle) {
+        if (cmHandleStatePerCmHandle.isEmpty()) {
+            return Collections.emptyList();
+        }
         final List<String> cmHandleIds = getCmHandleIds(cmHandleStatePerCmHandle);
-        log.info("Moving cm handles : {} into locked (for upgrade) state.", cmHandleIds);
+        log.info("Moving {} cm handles into locked (for upgrade) state: {} ", cmHandleIds.size(), cmHandleIds);
         try {
             lcmEventsCmHandleStateHandler.updateCmHandleStateBatch(cmHandleStatePerCmHandle);
             return CmHandleRegistrationResponse.createSuccessResponses(cmHandleIds);
@@ -384,5 +384,4 @@ public class CmHandleRegistrationService {
             ncmpServiceCmHandle.getDataProducerIdentifier());
     }
 
-
 }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImpl.java
index d566ae43cb..e7ec9cd13c 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImpl.java
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  Modifications Copyright (C) 2022 Bell Canada
  *  Modifications Copyright (C) 2024 TechMahindra Ltd.
  *  ================================================================================
@@ -62,26 +62,27 @@ public class InventoryPersistenceImpl extends NcmpPersistenceImpl implements Inv
     private static final int CMHANDLE_BATCH_SIZE = 100;
 
     private final CpsModuleService cpsModuleService;
-    private final CpsAnchorService cpsAnchorService;
     private final CpsValidator cpsValidator;
     private final CmHandleQueryService cmHandleQueryService;
 
     /**
      * initialize an inventory persistence object.
      *
-     * @param jsonObjectMapper json mapper object
-     * @param cpsDataService   cps data service instance
-     * @param cpsModuleService cps module service instance
-     * @param cpsValidator     cps validation service instance
-     * @param cpsAnchorService  cps anchor service instance
+     * @param cpsValidator         cps validation service instance
+     * @param jsonObjectMapper     json mapper object
+     * @param cpsAnchorService     cps anchor service instance
+     * @param cpsModuleService     cps module service instance
+     * @param cpsDataService       cps data service instance
+     * @param cmHandleQueryService cm handle query service instance
      */
-    public InventoryPersistenceImpl(final JsonObjectMapper jsonObjectMapper, final CpsDataService cpsDataService,
-                                    final CpsModuleService cpsModuleService, final CpsValidator cpsValidator,
+    public InventoryPersistenceImpl(final CpsValidator cpsValidator,
+                                    final JsonObjectMapper jsonObjectMapper,
                                     final CpsAnchorService cpsAnchorService,
+                                    final CpsModuleService cpsModuleService,
+                                    final CpsDataService cpsDataService,
                                     final CmHandleQueryService cmHandleQueryService) {
-        super(jsonObjectMapper, cpsDataService, cpsModuleService, cpsValidator);
+        super(jsonObjectMapper, cpsAnchorService, cpsDataService);
         this.cpsModuleService = cpsModuleService;
-        this.cpsAnchorService = cpsAnchorService;
         this.cpsValidator = cpsValidator;
         this.cmHandleQueryService = cmHandleQueryService;
     }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistence.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistence.java
index 714a7ca12f..f327edab17 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistence.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistence.java
@@ -1,6 +1,6 @@
 /*
  * ============LICENSE_START=======================================================
- * Copyright (C) 2022-2023 Nordix Foundation
+ * Copyright (C) 2022-2025 Nordix Foundation
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,9 +25,6 @@ import java.util.Collection;
 import org.onap.cps.api.model.DataNode;
 import org.onap.cps.api.parameters.FetchDescendantsOption;
 
-/**
- * DmiRegistryConstants class to be strictly used for DMI Related constants only.
- */
 public interface NcmpPersistence {
 
     String NCMP_DATASPACE_NAME = "NCMP-Admin";
@@ -44,20 +41,6 @@ public interface NcmpPersistence {
     void deleteListOrListElement(String listElementXpath);
 
     /**
-     * Method to delete a schema set.
-     *
-     * @param schemaSetName schema set name
-     */
-    void deleteSchemaSetWithCascade(String schemaSetName);
-
-    /**
-     * Method to delete multiple schema sets.
-     *
-     * @param schemaSetNames schema set names
-     */
-    void deleteSchemaSetsWithCascade(Collection<String> schemaSetNames);
-
-    /**
      * Get data node via xpath.
      *
      * @param xpath xpath
@@ -113,4 +96,12 @@ public interface NcmpPersistence {
      * @param dataNodeXpaths data node xpaths
      */
     void deleteDataNodes(Collection<String> dataNodeXpaths);
+
+    /**
+     * Deletes multiple anchors identified by their IDs.
+     *
+     * @param anchorIds ids of the anchors to be deleted
+     */
+    void deleteAnchors(Collection<String> anchorIds);
+
 }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistenceImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistenceImpl.java
index 6092d8b3b9..2232d7ce12 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistenceImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/NcmpPersistenceImpl.java
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2023 Nordix Foundation
+ *  Copyright (C) 2023-2025 Nordix Foundation
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -20,31 +20,25 @@
 
 package org.onap.cps.ncmp.impl.inventory;
 
-import static org.onap.cps.api.parameters.CascadeDeleteAllowed.CASCADE_DELETE_ALLOWED;
 import static org.onap.cps.api.parameters.FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS;
 
 import io.micrometer.core.annotation.Timed;
 import java.util.Collection;
 import lombok.RequiredArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
+import org.onap.cps.api.CpsAnchorService;
 import org.onap.cps.api.CpsDataService;
-import org.onap.cps.api.CpsModuleService;
-import org.onap.cps.api.exceptions.SchemaSetNotFoundException;
 import org.onap.cps.api.model.DataNode;
 import org.onap.cps.api.parameters.FetchDescendantsOption;
-import org.onap.cps.impl.utils.CpsValidator;
 import org.onap.cps.utils.JsonObjectMapper;
 import org.springframework.stereotype.Component;
 
-@Slf4j
 @RequiredArgsConstructor
 @Component
 public class NcmpPersistenceImpl implements NcmpPersistence {
 
     protected final JsonObjectMapper jsonObjectMapper;
+    protected final CpsAnchorService cpsAnchorService;
     protected final CpsDataService cpsDataService;
-    private final CpsModuleService cpsModuleService;
-    private final CpsValidator cpsValidator;
 
     @Override
     public void deleteListOrListElement(final String listElementXpath) {
@@ -53,27 +47,6 @@ public class NcmpPersistenceImpl implements NcmpPersistence {
     }
 
     @Override
-    @Timed(value = "cps.ncmp.inventory.persistence.schemaset.delete",
-            description = "Time taken to delete a schemaset")
-    public void deleteSchemaSetWithCascade(final String schemaSetName) {
-        try {
-            cpsValidator.validateNameCharacters(schemaSetName);
-            cpsModuleService.deleteSchemaSet(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, schemaSetName,
-                    CASCADE_DELETE_ALLOWED);
-        } catch (final SchemaSetNotFoundException schemaSetNotFoundException) {
-            log.warn("Schema set {} does not exist or already deleted", schemaSetName);
-        }
-    }
-
-    @Override
-    @Timed(value = "cps.ncmp.inventory.persistence.schemaset.delete.batch",
-        description = "Time taken to delete multiple schemaset")
-    public void deleteSchemaSetsWithCascade(final Collection<String> schemaSetNames) {
-        cpsValidator.validateNameCharacters(schemaSetNames);
-        cpsModuleService.deleteSchemaSetsWithCascade(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, schemaSetNames);
-    }
-
-    @Override
     @Timed(value = "cps.ncmp.inventory.persistence.datanode.get",
             description = "Time taken to get a data node (from ncmp dmi registry)")
     public Collection<DataNode> getDataNode(final String xpath) {
@@ -116,4 +89,9 @@ public class NcmpPersistenceImpl implements NcmpPersistence {
         cpsDataService.deleteDataNodes(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR, dataNodeXpaths, NO_TIMESTAMP);
     }
 
+    @Override
+    public void deleteAnchors(final Collection<String> anchorIds) {
+        cpsAnchorService.deleteAnchors(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, anchorIds);
+    }
+
 }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleOperationsUtils.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleOperationsUtils.java
index 994ca80287..e9f3d9b475 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleOperationsUtils.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleOperationsUtils.java
@@ -189,7 +189,7 @@ public class ModuleOperationsUtils {
                 .getLockReasonCategory()));
     }
 
-    public static String getUpgradedModuleSetTagFromLockReason(final CompositeState.LockReason lockReason) {
+    public static String getTargetModuleSetTagFromLockReason(final CompositeState.LockReason lockReason) {
         return getLockedCompositeStateDetails(lockReason).getOrDefault(MODULE_SET_TAG_KEY, "");
     }
 
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncService.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncService.java
index 3f92dc73f0..9534cf35b1 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncService.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncService.java
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  Modifications Copyright (C) 2024 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
@@ -26,24 +26,18 @@ import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NCMP_DMI_REGISTRY
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NCMP_DMI_REGISTRY_PARENT;
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME;
 
-import com.hazelcast.collection.ISet;
 import java.time.OffsetDateTime;
 import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
 import java.util.Map;
 import lombok.AllArgsConstructor;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import org.apache.logging.log4j.util.Strings;
 import org.onap.cps.api.CpsAnchorService;
 import org.onap.cps.api.CpsDataService;
 import org.onap.cps.api.CpsModuleService;
-import org.onap.cps.api.exceptions.SchemaSetNotFoundException;
+import org.onap.cps.api.exceptions.AlreadyDefinedException;
+import org.onap.cps.api.exceptions.DuplicatedYangResourceException;
 import org.onap.cps.api.model.ModuleReference;
-import org.onap.cps.api.parameters.CascadeDeleteAllowed;
-import org.onap.cps.ncmp.api.exceptions.NcmpException;
-import org.onap.cps.ncmp.api.inventory.models.CmHandleState;
 import org.onap.cps.ncmp.impl.inventory.models.YangModelCmHandle;
 import org.onap.cps.utils.ContentType;
 import org.onap.cps.utils.JsonObjectMapper;
@@ -54,15 +48,11 @@ import org.springframework.stereotype.Service;
 @RequiredArgsConstructor
 public class ModuleSyncService {
 
-    private static final Map<String, String> NO_NEW_MODULES = Collections.emptyMap();
-
     private final DmiModelOperations dmiModelOperations;
     private final CpsModuleService cpsModuleService;
     private final CpsDataService cpsDataService;
     private final CpsAnchorService cpsAnchorService;
     private final JsonObjectMapper jsonObjectMapper;
-    private final ISet<String> moduleSetTagsBeingProcessed;
-    private final Map<String, ModuleDelta> privateModuleSetCache = new HashMap<>();
 
     @AllArgsConstructor
     private static final class ModuleDelta {
@@ -71,42 +61,16 @@ public class ModuleSyncService {
     }
 
     /**
-     * This method creates a cm handle and initiates modules sync.
+     * Creates a CM handle and initiates the synchronization of modules to create a schema set and anchor.
      *
      * @param yangModelCmHandle the yang model of cm handle.
      */
     public void syncAndCreateSchemaSetAndAnchor(final YangModelCmHandle yangModelCmHandle) {
+        final String cmHandleId = yangModelCmHandle.getId();
         final String moduleSetTag = yangModelCmHandle.getModuleSetTag();
-        final ModuleDelta moduleDelta;
-        boolean isNewModuleSetTag = Strings.isNotBlank(moduleSetTag);
-        try {
-            if (privateModuleSetCache.containsKey(moduleSetTag)) {
-                moduleDelta = privateModuleSetCache.get(moduleSetTag);
-            } else {
-                if (isNewModuleSetTag) {
-                    if (moduleSetTagsBeingProcessed.add(moduleSetTag)) {
-                        log.info("Processing new module set tag {}", moduleSetTag);
-                    } else {
-                        isNewModuleSetTag = false;
-                        throw new NcmpException("Concurrent processing of module set tag " + moduleSetTag,
-                            moduleSetTag + " already being processed for cm handle " + yangModelCmHandle.getId());
-                    }
-                }
-                moduleDelta = getModuleDelta(yangModelCmHandle, moduleSetTag);
-            }
-            final String cmHandleId = yangModelCmHandle.getId();
-            cpsModuleService.createSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId,
-                moduleDelta.newModuleNameToContentMap, moduleDelta.allModuleReferences);
-            cpsAnchorService.createAnchor(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId, cmHandleId);
-            if (isNewModuleSetTag) {
-                final ModuleDelta noModuleDelta = new ModuleDelta(moduleDelta.allModuleReferences, NO_NEW_MODULES);
-                privateModuleSetCache.put(moduleSetTag, noModuleDelta);
-            }
-        } finally {
-            if (isNewModuleSetTag) {
-                moduleSetTagsBeingProcessed.remove(moduleSetTag);
-            }
-        }
+        final String schemaSetName = getSchemaSetName(cmHandleId, moduleSetTag);
+        syncAndCreateSchemaSet(yangModelCmHandle, schemaSetName);
+        cpsAnchorService.createAnchor(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, schemaSetName, cmHandleId);
     }
 
     /**
@@ -115,55 +79,61 @@ public class ModuleSyncService {
      * @param yangModelCmHandle the yang model of cm handle.
      */
     public void syncAndUpgradeSchemaSet(final YangModelCmHandle yangModelCmHandle) {
-        final String upgradedModuleSetTag = ModuleOperationsUtils.getUpgradedModuleSetTagFromLockReason(
+        final String cmHandleId = yangModelCmHandle.getId();
+        final String sourceModuleSetTag = yangModelCmHandle.getModuleSetTag();
+        final String targetModuleSetTag = ModuleOperationsUtils.getTargetModuleSetTagFromLockReason(
                 yangModelCmHandle.getCompositeState().getLockReason());
-        final ModuleDelta moduleDelta = getModuleDelta(yangModelCmHandle, upgradedModuleSetTag);
-        cpsModuleService.upgradeSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME,
-                yangModelCmHandle.getId(), moduleDelta.newModuleNameToContentMap, moduleDelta.allModuleReferences);
-        setCmHandleModuleSetTag(yangModelCmHandle, upgradedModuleSetTag);
+        if (sourceModuleSetTag.isEmpty() && targetModuleSetTag.isEmpty()) {
+            final ModuleDelta moduleDelta = getModuleDelta(yangModelCmHandle);
+            cpsModuleService.upgradeSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME,
+                    cmHandleId, moduleDelta.newModuleNameToContentMap, moduleDelta.allModuleReferences);
+        } else {
+            final String targetSchemaSetName = getSchemaSetName(cmHandleId, targetModuleSetTag);
+            syncAndCreateSchemaSet(yangModelCmHandle, targetSchemaSetName);
+            cpsAnchorService.updateAnchorSchemaSet(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId,
+                    targetSchemaSetName);
+            setCmHandleModuleSetTag(yangModelCmHandle, targetModuleSetTag);
+            log.info("Upgrading schema set for CM handle ID: {}, Source Tag: {}, Target Tag: {}",
+                cmHandleId, sourceModuleSetTag, targetModuleSetTag);
+        }
     }
 
-    /**
-     * Deletes the SchemaSet for schema set id if the SchemaSet Exists.
-     *
-     * @param schemaSetId the schema set id to be deleted
-     */
-    public void deleteSchemaSetIfExists(final String schemaSetId) {
-        try {
-            cpsModuleService.deleteSchemaSet(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, schemaSetId,
-                CascadeDeleteAllowed.CASCADE_DELETE_ALLOWED);
-            log.debug("SchemaSet for {} has been deleted. Ready to be recreated.", schemaSetId);
-        } catch (final SchemaSetNotFoundException e) {
-            log.debug("No SchemaSet for {}. Assuming CmHandle has not been previously Module Synced.", schemaSetId);
+    private void syncAndCreateSchemaSet(final YangModelCmHandle yangModelCmHandle, final String schemaSetName) {
+        if (isNewSchemaSet(schemaSetName)) {
+            final ModuleDelta moduleDelta = getModuleDelta(yangModelCmHandle);
+            try {
+                log.info("Creating Schema Set {} for CM Handle {}", schemaSetName, yangModelCmHandle.getId());
+                cpsModuleService.createSchemaSetFromModules(
+                        NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME,
+                        schemaSetName,
+                        moduleDelta.newModuleNameToContentMap,
+                        moduleDelta.allModuleReferences
+                );
+                log.info("Successfully created Schema Set {} for CM Handle {}",
+                    schemaSetName, yangModelCmHandle.getId());
+            } catch (final AlreadyDefinedException | DuplicatedYangResourceException exception) {
+                log.warn("Schema Set {} already exists, no need to (re)create it for {}",
+                    schemaSetName, yangModelCmHandle.getId());
+            }
         }
     }
 
-    public void clearPrivateModuleSetCache() {
-        privateModuleSetCache.clear();
+    private boolean isNewSchemaSet(final String schemaSetName) {
+        return !cpsModuleService.schemaSetExists(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, schemaSetName);
     }
 
-    private ModuleDelta getModuleDelta(final YangModelCmHandle yangModelCmHandle, final String targetModuleSetTag) {
-        final Map<String, String> newYangResources;
-        Collection<ModuleReference> allModuleReferences = getModuleReferencesByModuleSetTag(targetModuleSetTag);
-        if (allModuleReferences.isEmpty()) {
-            allModuleReferences = dmiModelOperations.getModuleReferences(yangModelCmHandle);
-            newYangResources = dmiModelOperations.getNewYangResourcesFromDmi(yangModelCmHandle,
-                    cpsModuleService.identifyNewModuleReferences(allModuleReferences));
-        } else {
-            log.info("Found other cm handle having same module set tag: {}", targetModuleSetTag);
-            newYangResources = NO_NEW_MODULES;
-        }
+    private ModuleDelta getModuleDelta(final YangModelCmHandle yangModelCmHandle) {
+        final Collection<ModuleReference> allModuleReferences =
+            dmiModelOperations.getModuleReferences(yangModelCmHandle);
+        final Collection<ModuleReference> newModuleReferences =
+                cpsModuleService.identifyNewModuleReferences(allModuleReferences);
+        final Map<String, String> newYangResources = dmiModelOperations.getNewYangResourcesFromDmi(yangModelCmHandle,
+                newModuleReferences);
+        log.debug("Module delta calculated for CM handle ID: {}. All references: {}. New modules: {}",
+            yangModelCmHandle.getId(), allModuleReferences, newYangResources.keySet());
         return new ModuleDelta(allModuleReferences, newYangResources);
     }
 
-    private Collection<ModuleReference> getModuleReferencesByModuleSetTag(final String moduleSetTag) {
-        if (Strings.isBlank(moduleSetTag)) {
-            return Collections.emptyList();
-        }
-        return cpsModuleService.getModuleReferencesByAttribute(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
-                Map.of("module-set-tag", moduleSetTag), Map.of("cm-handle-state", CmHandleState.READY.name()));
-    }
-
     private void setCmHandleModuleSetTag(final YangModelCmHandle yangModelCmHandle, final String newModuleSetTag) {
         final String jsonForUpdate = jsonObjectMapper.asJsonString(Map.of(
                 "cm-handles", Map.of("id", yangModelCmHandle.getId(), "module-set-tag", newModuleSetTag)));
@@ -171,4 +141,8 @@ public class ModuleSyncService {
                 jsonForUpdate, OffsetDateTime.now(), ContentType.JSON);
     }
 
+    private static String getSchemaSetName(final String cmHandleId, final String moduleSetTag) {
+        return moduleSetTag.isEmpty() ? cmHandleId : moduleSetTag;
+    }
+
 }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasks.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasks.java
index 5f289c2c01..40404b719a 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasks.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasks.java
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -109,13 +109,12 @@ public class ModuleSyncTasks {
             if (inUpgrade) {
                 moduleSyncService.syncAndUpgradeSchemaSet(yangModelCmHandle);
             } else {
-                moduleSyncService.deleteSchemaSetIfExists(yangModelCmHandle.getId());
                 moduleSyncService.syncAndCreateSchemaSetAndAnchor(yangModelCmHandle);
             }
             compositeState.setLockReason(null);
             return CmHandleState.READY;
         } catch (final Exception e) {
-            log.warn("Processing of {} module failed due to reason {}.", yangModelCmHandle.getId(), e.getMessage());
+            log.warn("Processing of {} failed,reason : {}.", yangModelCmHandle.getId(), e.getMessage());
             final LockReasonCategory lockReasonCategory = inUpgrade
                     ? LockReasonCategory.MODULE_UPGRADE_FAILED
                     : LockReasonCategory.MODULE_SYNC_FAILED;
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfig.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfig.java
index d6ac242b30..c05944f66e 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfig.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfig.java
@@ -1,6 +1,6 @@
 /*
  * ============LICENSE_START========================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -20,13 +20,10 @@
 
 package org.onap.cps.ncmp.impl.inventory.sync;
 
-import com.hazelcast.collection.ISet;
 import com.hazelcast.config.MapConfig;
 import com.hazelcast.config.QueueConfig;
-import com.hazelcast.config.SetConfig;
 import com.hazelcast.map.IMap;
 import java.util.concurrent.BlockingQueue;
-import lombok.extern.slf4j.Slf4j;
 import org.onap.cps.ncmp.impl.cache.HazelcastCacheConfig;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -34,7 +31,6 @@ import org.springframework.context.annotation.Configuration;
 /**
  * Core infrastructure of the hazelcast distributed caches for Module Sync and Data Sync use cases.
  */
-@Slf4j
 @Configuration
 public class SynchronizationCacheConfig extends HazelcastCacheConfig {
 
@@ -45,8 +41,6 @@ public class SynchronizationCacheConfig extends HazelcastCacheConfig {
     private static final MapConfig moduleSyncStartedConfig =
             createMapConfigWithTimeToLiveInSeconds("moduleSyncStartedConfig", MODULE_SYNC_STARTED_TTL_SECS);
     private static final MapConfig dataSyncSemaphoresConfig = createMapConfig("dataSyncSemaphoresConfig");
-    private static final SetConfig moduleSetTagsBeingProcessedConfig
-        = createSetConfig("moduleSetTagsBeingProcessedConfig");
 
     /**
      * Module Sync Distributed Queue Instance.
@@ -78,14 +72,4 @@ public class SynchronizationCacheConfig extends HazelcastCacheConfig {
         return getOrCreateHazelcastInstance(dataSyncSemaphoresConfig).getMap("dataSyncSemaphores");
     }
 
-    /**
-     * Collection of (new) module set tags being processed.
-     * To prevent processing on multiple threads of same tag
-     *
-     * @return set of module set tags being processed
-     */
-    @Bean
-    public ISet<String> moduleSetTagsBeingProcessed() {
-        return getOrCreateHazelcastInstance(moduleSetTagsBeingProcessedConfig).getSet("moduleSetTagsBeingProcessed");
-    }
 }
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationServiceSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationServiceSpec.groovy
index ff190cc1ca..953e1c7d0e 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationServiceSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/CmHandleRegistrationServiceSpec.groovy
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2021-2024 Nordix Foundation
+ *  Copyright (C) 2021-2025 Nordix Foundation
  *  Modifications Copyright (C) 2022 Bell Canada
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
@@ -23,7 +23,10 @@ package org.onap.cps.ncmp.impl.inventory
 
 import com.hazelcast.map.IMap
 import org.onap.cps.api.CpsDataService
-import org.onap.cps.api.CpsModuleService
+import org.onap.cps.api.exceptions.AlreadyDefinedException
+import org.onap.cps.api.exceptions.CpsException
+import org.onap.cps.api.exceptions.DataNodeNotFoundException
+import org.onap.cps.api.exceptions.DataValidationException
 import org.onap.cps.ncmp.api.exceptions.DmiRequestException
 import org.onap.cps.ncmp.api.inventory.DataStoreSyncState
 import org.onap.cps.ncmp.api.inventory.models.CmHandleRegistrationResponse
@@ -36,11 +39,6 @@ import org.onap.cps.ncmp.api.inventory.models.CmHandleState
 import org.onap.cps.ncmp.impl.inventory.models.YangModelCmHandle
 import org.onap.cps.ncmp.impl.inventory.sync.lcm.LcmEventsCmHandleStateHandler
 import org.onap.cps.ncmp.impl.inventory.trustlevel.TrustLevelManager
-import org.onap.cps.api.exceptions.AlreadyDefinedException
-import org.onap.cps.api.exceptions.CpsException
-import org.onap.cps.api.exceptions.DataNodeNotFoundException
-import org.onap.cps.api.exceptions.DataValidationException
-import org.onap.cps.api.exceptions.SchemaSetNotFoundException
 import spock.lang.Specification
 
 import static org.onap.cps.ncmp.api.NcmpResponseStatus.CM_HANDLES_NOT_FOUND
@@ -53,7 +51,6 @@ import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NFP_OPERATIONAL_D
 class CmHandleRegistrationServiceSpec extends Specification {
 
     def ncmpServiceCmHandle = new NcmpServiceCmHandle(cmHandleId: 'some-cm-handle-id')
-    def mockCpsModuleService = Mock(CpsModuleService)
     def mockNetworkCmProxyDataServicePropertyHandler = Mock(CmHandleRegistrationServicePropertyHandler)
     def mockInventoryPersistence = Mock(InventoryPersistence)
     def mockCmHandleQueries = Mock(CmHandleQueryService)
@@ -80,33 +77,43 @@ class CmHandleRegistrationServiceSpec extends Specification {
             def dmiRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server')
             dmiRegistration.setCreatedCmHandles([new NcmpServiceCmHandle(cmHandleId: 'cmhandle-1', publicProperties: ['publicProp1': 'value'], dmiProperties: [:])])
             dmiRegistration.setUpdatedCmHandles([new NcmpServiceCmHandle(cmHandleId: 'cmhandle-2', publicProperties: ['publicProp1': 'value'], dmiProperties: [:])])
-            dmiRegistration.setRemovedCmHandles(['cmhandle-2'])
-            dmiRegistration.setUpgradedCmHandles(new UpgradedCmHandles(cmHandles: ['cmhandle-3'], moduleSetTag: 'some-module-set-tag'))
-        and: 'cm handles are persisted'
+            dmiRegistration.setRemovedCmHandles(['cmhandle-3'])
+            dmiRegistration.setUpgradedCmHandles(new UpgradedCmHandles(cmHandles: ['cmhandle-4', 'cmhandle-5'], moduleSetTag: moduleSetTagForUpgrade))
+        and: 'cm handles 2,3 and 4 already exist in the inventory'
             mockInventoryPersistence.getYangModelCmHandles(['cmhandle-2']) >> [new YangModelCmHandle()]
-            mockInventoryPersistence.getYangModelCmHandle('cmhandle-3') >> new YangModelCmHandle(id: 'cmhandle-3', moduleSetTag: '', compositeState: new CompositeState(cmHandleState: CmHandleState.READY))
-        and: 'cm handle is in READY state'
-            mockCmHandleQueries.cmHandleHasState('cmhandle-3', CmHandleState.READY) >> true
-        and: 'cm handles is present in in-progress map'
-            mockModuleSyncStartedOnCmHandles.containsKey('cmhandle-2') >> true
+            mockInventoryPersistence.getYangModelCmHandles(['cmhandle-3']) >> [new YangModelCmHandle()]
+            mockInventoryPersistence.getYangModelCmHandle('cmhandle-4') >> new YangModelCmHandle(id: 'cmhandle-4', moduleSetTag: '', compositeState: new CompositeState(cmHandleState: CmHandleState.READY))
+        and: 'cm handle 5 also exist but already has the new module set tag (upgrade to)'
+            mockInventoryPersistence.getYangModelCmHandle('cmhandle-5') >> new YangModelCmHandle(id: 'cmhandle-5', moduleSetTag: moduleSetTagForUpgrade , compositeState: new CompositeState(cmHandleState: CmHandleState.READY))
+        and: 'all cm handles are in READY state'
+            mockCmHandleQueries.cmHandleHasState(_, CmHandleState.READY) >> true
+        and: 'cm handle to be removed is in progress map'
+            mockModuleSyncStartedOnCmHandles.containsKey('cmhandle-3') >> true
         when: 'registration is processed'
-            objectUnderTest.updateDmiRegistration(dmiRegistration)
+            def result = objectUnderTest.updateDmiRegistration(dmiRegistration)
         then: 'cm-handles are removed first'
             1 * objectUnderTest.processRemovedCmHandles(*_)
         and: 'de-registered cm handle entry is removed from in progress map'
-            1 * mockModuleSyncStartedOnCmHandles.removeAsync('cmhandle-2')
-        then: 'cm-handles are updated'
+            1 * mockModuleSyncStartedOnCmHandles.removeAsync('cmhandle-3')
+        then: 'updated cm handles are processed by the property handler service'
             1 * objectUnderTest.processUpdatedCmHandles(*_)
-            1 * mockNetworkCmProxyDataServicePropertyHandler.updateCmHandleProperties(*_) >> []
+            1 * mockNetworkCmProxyDataServicePropertyHandler.updateCmHandleProperties(*_) >> [CmHandleRegistrationResponse.createSuccessResponse('cmhandle-2')]
         then: 'cm-handles are upgraded'
             1 * objectUnderTest.processUpgradedCmHandles(*_)
+        and: 'result contains the correct cm handles for each operation'
+            assert result.createdCmHandles.cmHandle == ['cmhandle-1']
+            assert result.updatedCmHandles.cmHandle == ['cmhandle-2']
+            assert result.removedCmHandles.cmHandle == ['cmhandle-3']
+            assert result.upgradedCmHandles.cmHandle as Set == ['cmhandle-4', 'cmhandle-5'] as Set
+        where: 'upgrade with and without module set tag'
+            moduleSetTagForUpgrade << ['some tag', '']
     }
 
     def 'DMI Registration upgrade operation with upgrade node state #scenario'() {
         given: 'a registration with upgrade operation'
             def dmiRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server')
             dmiRegistration.setUpgradedCmHandles(new UpgradedCmHandles(cmHandles: ['cmhandle-3'], moduleSetTag: 'some-module-set-tag'))
-        and: 'exception while checking cm handle state'
+        and: 'cm handle has the state #cmHandleState'
             mockInventoryPersistence.getYangModelCmHandle('cmhandle-3') >> new YangModelCmHandle(id: 'cmhandle-3', moduleSetTag: '', compositeState: new CompositeState(cmHandleState: cmHandleState))
         when: 'registration is processed'
             def result = objectUnderTest.updateDmiRegistration(dmiRegistration)
@@ -134,6 +141,21 @@ class CmHandleRegistrationServiceSpec extends Specification {
             'cm handle is invalid' | new DataValidationException('some error message', 'some error details')  || '110'
     }
 
+    def 'DMI Registration upgrade with exception while updating CM-handle state'() {
+        given: 'a registration with upgrade operation'
+            def dmiRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server')
+            dmiRegistration.setUpgradedCmHandles(new UpgradedCmHandles(cmHandles: ['cmhandle-3'], moduleSetTag: 'some-module-set-tag'))
+        and: 'cm handle has the state READY'
+            mockInventoryPersistence.getYangModelCmHandle('cmhandle-3') >> new YangModelCmHandle(id: 'cmhandle-3', moduleSetTag: '', compositeState: new CompositeState(cmHandleState: CmHandleState.READY))
+        and: 'exception will occur while updating cm handle state to LOCKED for upgrade'
+            mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch(_) >> { throw new RuntimeException() }
+        when: 'registration is processed'
+            def result = objectUnderTest.updateDmiRegistration(dmiRegistration)
+        then: 'upgrade operation contains expected error code'
+            assert result.upgradedCmHandles[0].status == Status.FAILURE
+            assert result.upgradedCmHandles[0].ncmpResponseStatus == UNKNOWN_ERROR
+    }
+
     def 'Create CM-handle Validation: Registration with valid Service names: #scenario'() {
         given: 'a registration '
             def dmiPluginRegistration = new DmiPluginRegistration(dmiPlugin: dmiPlugin, dmiModelPlugin: dmiModelPlugin,
@@ -276,18 +298,15 @@ class CmHandleRegistrationServiceSpec extends Specification {
             assert response.updatedCmHandles.containsAll(updateOperationResponse)
     }
 
-    def 'Remove CmHandle Successfully: #scenario'() {
-        given: 'a registration'
+    def 'Remove CmHandle Successfully'() {
+        given: 'a registration update to delete a cm handle'
             def dmiPluginRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server', removedCmHandles: ['cmhandle'])
-        and: '#scenario'
-            mockCpsModuleService.deleteSchemaSetsWithCascade(_, ['cmhandle']) >>  { if (!schemaSetExist) { throw new SchemaSetNotFoundException('', '') } }
-        when: 'registration is updated to delete cmhandle'
+        when: 'the registration is updated'
             def response = objectUnderTest.updateDmiRegistration(dmiPluginRegistration)
-        then: 'the cmHandle state is updated to "DELETING"'
-            1 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch(_) >>
-                { args -> args[0].values()[0] == CmHandleState.DELETING }
-        then: 'method to delete relevant schema set is called once'
-            1 * mockInventoryPersistence.deleteSchemaSetsWithCascade(_)
+        then: 'the cmHandle state is set to "DELETING"'
+            1 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch(_) >> { args -> args[0].values()[0] == CmHandleState.DELETING }
+        then: 'method to delete anchors is called once'
+            1 * mockInventoryPersistence.deleteAnchors(_)
         and: 'method to delete relevant list/list element is called once'
             1 * mockInventoryPersistence.deleteDataNodes(_)
         and: 'successful response is received'
@@ -297,14 +316,7 @@ class CmHandleRegistrationServiceSpec extends Specification {
                 assert it.cmHandle == 'cmhandle'
             }
         and: 'the cmHandle state is updated to "DELETED"'
-            1 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch(_) >>
-                { args -> args[0].values()[0] == CmHandleState.DELETED }
-        and: 'No cm handles state updates for "upgraded cm handles"'
-            1 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch([:])
-        where:
-            scenario                                            | schemaSetExist
-            'schema-set exists and can be deleted successfully' | true
-            'schema-set does not exist'                         | false
+            1 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch(_) >>  { args -> args[0].values()[0] == CmHandleState.DELETED }
     }
 
     def 'Remove CmHandle: Partial Success'() {
@@ -314,10 +326,11 @@ class CmHandleRegistrationServiceSpec extends Specification {
         and: 'cm handles to be deleted in the progress map'
             mockModuleSyncStartedOnCmHandles.containsKey("cmhandle1") >> true
             mockModuleSyncStartedOnCmHandles.containsKey("cmhandle3") >> true
-        and: 'cm-handle deletion fails on batch'
-            mockInventoryPersistence.deleteDataNodes(_) >> { throw new RuntimeException("Failed") }
-        and: 'cm-handle deletion is successful for 1st and 3rd; failed for 2nd'
-            mockInventoryPersistence.deleteDataNode("/dmi-registry/cm-handles[@id='cmhandle2']") >> { throw new RuntimeException("Failed") }
+        and: 'delete fails for batch. Retry only fails for and cm handle 2'
+            mockInventoryPersistence.deleteDataNodes(_) >> { throw new RuntimeException("Batch Failed") }
+                                                        >> { /* cm handle 1 is OK */ }
+                                                        >> { throw new RuntimeException("Cm handle 2 Failed")}
+                                                        >> { /* cm handle 3 is OK */ }
         when: 'registration is updated to delete cmhandles'
             def response = objectUnderTest.updateDmiRegistration(dmiPluginRegistration)
         then: 'the cmHandle states are all updated to "DELETING"'
@@ -343,7 +356,7 @@ class CmHandleRegistrationServiceSpec extends Specification {
             with(response.removedCmHandles[1]) {
                 assert it.status == Status.FAILURE
                 assert it.ncmpResponseStatus == UNKNOWN_ERROR
-                assert it.errorText == 'Failed'
+                assert it.errorText == 'Cm handle 2 Failed'
                 assert it.cmHandle == 'cmhandle2'
             }
         and: 'the cmHandle state is updated to DELETED for 1st and 3rd'
@@ -351,40 +364,11 @@ class CmHandleRegistrationServiceSpec extends Specification {
                 assert it.size() == 2
                 assert it.every { entry -> entry.value == CmHandleState.DELETED }
             })
-        and: 'No cm handles state updates for "upgraded cm handles"'
-            1 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch([:])
-    }
-
-    def 'Remove CmHandle Error Handling: Schema Set Deletion failed'() {
-        given: 'a registration'
-            def dmiPluginRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server',
-                removedCmHandles: ['cmhandle'])
-        and: 'schema set batch deletion failed with unknown error'
-            mockInventoryPersistence.deleteSchemaSetsWithCascade(_) >> { throw new RuntimeException('Failed') }
-        and: 'schema set single deletion failed with unknown error'
-            mockInventoryPersistence.deleteSchemaSetWithCascade(_) >> { throw new RuntimeException('Failed') }
-        when: 'registration is updated to delete cmhandle'
-            def response = objectUnderTest.updateDmiRegistration(dmiPluginRegistration)
-        then: 'no exception is thrown'
-            noExceptionThrown()
-        and: 'cm-handle is not deleted'
-            0 * mockInventoryPersistence.deleteDataNodes(_)
-        and: 'the cmHandle state is not updated to "DELETED"'
-            0 * mockLcmEventsCmHandleStateHandler.updateCmHandleStateBatch([yangModelCmHandle: CmHandleState.DELETED])
-        and: 'a failure response is received'
-            assert response.removedCmHandles.size() == 1
-            with(response.removedCmHandles[0]) {
-                assert it.status == Status.FAILURE
-                assert it.cmHandle == 'cmhandle'
-                assert it.errorText == 'Failed'
-                assert it.ncmpResponseStatus == UNKNOWN_ERROR
-            }
     }
 
     def 'Remove CmHandle Error Handling: #scenario'() {
         given: 'a registration'
-            def dmiPluginRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server',
-                removedCmHandles: ['cmhandle'])
+            def dmiPluginRegistration = new DmiPluginRegistration(dmiPlugin: 'my-server', removedCmHandles: ['cmhandle'])
         and: 'cm-handle deletion fails on batch'
             mockInventoryPersistence.deleteDataNodes(_) >> { throw deleteListElementException }
         and: 'cm-handle deletion fails on individual delete'
@@ -408,7 +392,7 @@ class CmHandleRegistrationServiceSpec extends Specification {
         'an unexpected exception'    | new RuntimeException('Failed')            || UNKNOWN_ERROR        | 'Failed'
     }
 
-    def 'Set Cm Handle Data Sync Enabled Flag where data sync flag is  #scenario'() {
+    def 'Set Cm Handle Data Sync Enabled Flag where data sync flag is #scenario'() {
         given: 'an existing cm handle composite state'
             def compositeState = new CompositeState(cmHandleState: CmHandleState.READY, dataSyncEnabled: initialDataSyncEnabledFlag,
                 dataStores: CompositeState.DataStores.builder()
@@ -429,7 +413,7 @@ class CmHandleRegistrationServiceSpec extends Specification {
             saveCmHandleStateExpectedNumberOfInvocations * mockInventoryPersistence.saveCmHandleState('some-cm-handle-id', compositeState)
         where: 'the following data sync enabled flag is used'
             scenario                                              | dataSyncEnabledFlag | initialDataSyncEnabledFlag | initialDataSyncState               || expectedDataStoreSyncState         | deleteDataNodeExpectedNumberOfInvocation | saveCmHandleStateExpectedNumberOfInvocations
-            'enabled'                                             | true                | false                      | DataStoreSyncState.NONE_REQUESTED || DataStoreSyncState.UNSYNCHRONIZED | 0 | 1
+            'enabled'                                             | true                | false                      | DataStoreSyncState.NONE_REQUESTED  || DataStoreSyncState.UNSYNCHRONIZED  | 0                                        | 1
             'disabled'                                            | false               | true                       | DataStoreSyncState.UNSYNCHRONIZED  || DataStoreSyncState.NONE_REQUESTED  | 0                                        | 1
             'disabled where sync-state is currently SYNCHRONIZED' | false               | true                       | DataStoreSyncState.SYNCHRONIZED    || DataStoreSyncState.NONE_REQUESTED  | 1                                        | 1
             'is set to existing flag state'                       | true                | true                       | DataStoreSyncState.UNSYNCHRONIZED  || DataStoreSyncState.UNSYNCHRONIZED  | 0                                        | 0
@@ -448,6 +432,4 @@ class CmHandleRegistrationServiceSpec extends Specification {
             0 * mockInventoryPersistence.saveCmHandleState(_, _)
     }
 
-
-
 }
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImplSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImplSpec.groovy
index 619da70bf2..d8d92e99f5 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImplSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/InventoryPersistenceImplSpec.groovy
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  Modifications Copyright (C) 2022 Bell Canada
  *  Modifications Copyright (C) 2024 TechMahindra Ltd.
  *  ================================================================================
@@ -23,38 +23,36 @@
 package org.onap.cps.ncmp.impl.inventory
 
 import com.fasterxml.jackson.databind.ObjectMapper
+import java.time.OffsetDateTime
+import java.time.ZoneOffset
+import java.time.format.DateTimeFormatter
 import org.onap.cps.api.CpsAnchorService
 import org.onap.cps.api.CpsDataService
 import org.onap.cps.api.CpsModuleService
 import org.onap.cps.api.exceptions.DataNodeNotFoundException
 import org.onap.cps.api.exceptions.DataValidationException
+import org.onap.cps.api.model.DataNode
+import org.onap.cps.api.model.ModuleDefinition
+import org.onap.cps.api.model.ModuleReference
+import org.onap.cps.api.parameters.FetchDescendantsOption
 import org.onap.cps.impl.utils.CpsValidator
 import org.onap.cps.ncmp.api.exceptions.CmHandleNotFoundException
 import org.onap.cps.ncmp.api.inventory.models.CompositeState
 import org.onap.cps.ncmp.api.inventory.models.CmHandleState
 import org.onap.cps.ncmp.impl.inventory.models.YangModelCmHandle
 import org.onap.cps.ncmp.impl.utils.YangDataConverter
-import org.onap.cps.api.parameters.CascadeDeleteAllowed
-import org.onap.cps.api.parameters.FetchDescendantsOption
-import org.onap.cps.api.model.DataNode
-import org.onap.cps.api.model.ModuleDefinition
-import org.onap.cps.api.model.ModuleReference
 import org.onap.cps.utils.ContentType
 import org.onap.cps.utils.JsonObjectMapper
 import spock.lang.Shared
 import spock.lang.Specification
 
-import java.time.OffsetDateTime
-import java.time.ZoneOffset
-import java.time.format.DateTimeFormatter
-
+import static org.onap.cps.api.parameters.FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS
+import static org.onap.cps.api.parameters.FetchDescendantsOption.OMIT_DESCENDANTS
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NCMP_DATASPACE_NAME
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NCMP_DMI_REGISTRY_ANCHOR
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NCMP_DMI_REGISTRY_PARENT
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME
 import static org.onap.cps.ncmp.impl.inventory.NcmpPersistence.NO_TIMESTAMP
-import static org.onap.cps.api.parameters.FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS
-import static org.onap.cps.api.parameters.FetchDescendantsOption.OMIT_DESCENDANTS
 
 class InventoryPersistenceImplSpec extends Specification {
 
@@ -72,8 +70,7 @@ class InventoryPersistenceImplSpec extends Specification {
 
     def mockYangDataConverter = Mock(YangDataConverter)
 
-    def objectUnderTest = new InventoryPersistenceImpl(spiedJsonObjectMapper, mockCpsDataService, mockCpsModuleService,
-            mockCpsValidator, mockCpsAnchorService, mockCmHandleQueries)
+    def objectUnderTest = new InventoryPersistenceImpl(mockCpsValidator, spiedJsonObjectMapper, mockCpsAnchorService, mockCpsModuleService, mockCpsDataService, mockCmHandleQueries)
 
     def formattedDateAndTime = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSZ")
             .format(OffsetDateTime.of(2022, 12, 31, 20, 30, 40, 1, ZoneOffset.UTC))
@@ -294,24 +291,6 @@ class InventoryPersistenceImplSpec extends Specification {
             1 * mockCpsDataService.deleteListOrListElement(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,'sample xPath',null)
     }
 
-    def 'Delete schema set with a valid schema set name'() {
-        when: 'the method to delete schema set is called with valid schema set name'
-            objectUnderTest.deleteSchemaSetWithCascade('validSchemaSetName')
-        then: 'the module service to delete schemaSet is invoked once'
-            1 * mockCpsModuleService.deleteSchemaSet(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'validSchemaSetName', CascadeDeleteAllowed.CASCADE_DELETE_ALLOWED)
-        and: 'the schema set name is validated'
-            1 * mockCpsValidator.validateNameCharacters('validSchemaSetName')
-    }
-
-    def 'Delete multiple schema sets with valid schema set names'() {
-        when: 'the method to delete schema sets is called with valid schema set names'
-            objectUnderTest.deleteSchemaSetsWithCascade(['validSchemaSetName1', 'validSchemaSetName2'])
-        then: 'the module service to delete schema sets is invoked once'
-            1 * mockCpsModuleService.deleteSchemaSetsWithCascade(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, ['validSchemaSetName1', 'validSchemaSetName2'])
-        and: 'the schema set names are validated'
-            1 * mockCpsValidator.validateNameCharacters(['validSchemaSetName1', 'validSchemaSetName2'])
-    }
-
     def 'Get data node via xPath'() {
         when: 'the method to get data nodes is called'
             objectUnderTest.getDataNode('sample xPath')
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncServiceSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncServiceSpec.groovy
index 67cc4edd83..f8adfe5578 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncServiceSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncServiceSpec.groovy
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -20,20 +20,17 @@
 
 package org.onap.cps.ncmp.impl.inventory.sync
 
-import com.hazelcast.collection.ISet
 import org.onap.cps.api.CpsAnchorService
 import org.onap.cps.api.CpsDataService
 import org.onap.cps.api.CpsModuleService
-import org.onap.cps.ncmp.api.exceptions.NcmpException
+import org.onap.cps.api.exceptions.AlreadyDefinedException
+import org.onap.cps.api.exceptions.DuplicatedYangResourceException
+import org.onap.cps.api.model.ModuleReference
 import org.onap.cps.ncmp.api.inventory.models.CompositeStateBuilder
 import org.onap.cps.ncmp.api.inventory.models.NcmpServiceCmHandle
 import org.onap.cps.ncmp.impl.inventory.CmHandleQueryService
 import org.onap.cps.ncmp.api.inventory.models.CmHandleState
 import org.onap.cps.ncmp.impl.inventory.models.YangModelCmHandle
-import org.onap.cps.ncmp.impl.inventory.sync.ModuleSyncService.ModuleDelta
-import org.onap.cps.api.parameters.CascadeDeleteAllowed
-import org.onap.cps.api.exceptions.SchemaSetNotFoundException
-import org.onap.cps.api.model.ModuleReference
 import org.onap.cps.utils.JsonObjectMapper
 import spock.lang.Specification
 
@@ -48,18 +45,8 @@ class ModuleSyncServiceSpec extends Specification {
     def mockCmHandleQueries = Mock(CmHandleQueryService)
     def mockCpsDataService = Mock(CpsDataService)
     def mockJsonObjectMapper = Mock(JsonObjectMapper)
-    def mockModuleSetTagsBeingProcessed = Mock(ISet<String>);
 
-    def objectUnderTest = new ModuleSyncService(mockDmiModelOperations, mockCpsModuleService, mockCpsDataService, mockCpsAnchorService, mockJsonObjectMapper, mockModuleSetTagsBeingProcessed)
-
-    def expectedDataspaceName = NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME
-
-    def setup() {
-        // Allow tags for al test except 'duplicate-processing-tag' to be added to processing semaphore
-        mockModuleSetTagsBeingProcessed.add('new-tag') >> true
-        mockModuleSetTagsBeingProcessed.add('same-tag') >> true
-        mockModuleSetTagsBeingProcessed.add('cached-tag') >> true
-    }
+    def objectUnderTest = new ModuleSyncService(mockDmiModelOperations, mockCpsModuleService, mockCpsDataService, mockCpsAnchorService, mockJsonObjectMapper)
 
     def 'Sync models for a NEW cm handle using module set tags: #scenario.'() {
         given: 'a cm handle to be synced'
@@ -71,26 +58,24 @@ class ModuleSyncServiceSpec extends Specification {
             mockDmiModelOperations.getNewYangResourcesFromDmi(yangModelCmHandle, identifiedNewModuleReferences) >> newModuleNameContentToMap
         and: 'the module service identifies #identifiedNewModuleReferences.size() new modules'
             mockCpsModuleService.identifyNewModuleReferences(moduleReferences) >> identifiedNewModuleReferences
-        and: 'the service returns a list of module references when queried with the specified attributes'
-            mockCpsModuleService.getModuleReferencesByAttribute(*_) >> existingModuleReferences
         when: 'module sync is triggered'
             objectUnderTest.syncAndCreateSchemaSetAndAnchor(yangModelCmHandle)
         then: 'create schema set from module is invoked with correct parameters'
-            1 * mockCpsModuleService.createSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'ch-1', newModuleNameContentToMap, moduleReferences)
+            1 * mockCpsModuleService.createSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, expectedSchemaSetName, newModuleNameContentToMap, moduleReferences)
         and: 'anchor is created with the correct parameters'
-            1 * mockCpsAnchorService.createAnchor(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'ch-1', 'ch-1')
+            1 * mockCpsAnchorService.createAnchor(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, expectedSchemaSetName, 'ch-1')
         where: 'the following parameters are used'
-            scenario                  | identifiedNewModuleReferences         | newModuleNameContentToMap     | moduleSetTag | existingModuleReferences
-            'one new module, new tag' | [new ModuleReference('module1', '1')] | [module1: 'some yang source'] | ''           | []
-            'no new module, new tag'  | []                                    | [:]                           | 'new-tag'    | []
-            'same tag'                | []                                    | [:]                           | 'same-tag'   | [new ModuleReference('module1', '1'), new ModuleReference('module2', '2')]
+            scenario                  | identifiedNewModuleReferences         | newModuleNameContentToMap     | moduleSetTag | existingModuleReferences                                                   || expectedSchemaSetName
+            'one new module, new tag' | [new ModuleReference('module1', '1')] | [module1: 'some yang source'] | ''           | []                                                                         || 'ch-1'
+            'no new module, new tag'  | []                                    | [:]                           | 'new-tag'    | []                                                                         || 'new-tag'
+            'same tag'                | []                                    | [:]                           | 'same-tag'   | [new ModuleReference('module1', '1'), new ModuleReference('module2', '2')] || 'same-tag'
     }
 
-    def 'Attempt Sync models for a cm handle with exception and #scenario module set tag'() {
+    def 'Attempt Sync models for a cm handle with exception and #scenario module set tag.'() {
         given: 'a cm handle to be synced'
             def yangModelCmHandle = createAdvisedCmHandle(moduleSetTag)
-        and: 'the service returns a list of module references when queried with the specified attributes'
-            mockCpsModuleService.getModuleReferencesByAttribute(*_) >> [new ModuleReference('module1', '1')]
+        and: 'dmi returns no new yang resources'
+            mockDmiModelOperations.getNewYangResourcesFromDmi(*_) >> [:]
         and: 'exception occurs when trying to store result'
             def testException = new RuntimeException('test')
             mockCpsModuleService.createSchemaSetFromModules(*_) >> { throw testException }
@@ -99,130 +84,75 @@ class ModuleSyncServiceSpec extends Specification {
         then: 'the same exception is thrown up'
             def exceptionThrown = thrown(Exception)
             assert testException == exceptionThrown
-        and: 'module set tag is removed from processing semaphores only when needed'
-            expectedCallsToRemoveTag * mockModuleSetTagsBeingProcessed.remove('new-tag')
         where: 'following module set tags are used'
-            scenario  | moduleSetTag || expectedCallsToRemoveTag
-            'with'    | 'new-tag'    || 1
-            'without' | ' '          || 0
-    }
-
-    def 'Sync models for a cm handle with previously cached module set tag.'() {
-        given: 'a cm handle to be synced'
-            def yangModelCmHandle = createAdvisedCmHandle('cached-tag')
-        and: 'The module set tag exists in the private cache'
-            def moduleReferences = [ new ModuleReference('module1','1') ]
-            def cachedModuleDelta = new ModuleDelta(moduleReferences, [:])
-            objectUnderTest.privateModuleSetCache.put('cached-tag', cachedModuleDelta)
-        when: 'module sync is triggered'
-            objectUnderTest.syncAndCreateSchemaSetAndAnchor(yangModelCmHandle)
-        then: 'create schema set from module is invoked with correct parameters'
-            1 * mockCpsModuleService.createSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'ch-1', [:], moduleReferences)
-        and: 'anchor is created with the correct parameters'
-            1 * mockCpsAnchorService.createAnchor(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'ch-1', 'ch-1')
+            scenario  | moduleSetTag
+            'with'    | 'new-tag'
+            'without' | ''
     }
 
-    def 'Attempt to sync using a module set tag already being processed by a different instance or thread.'() {
+    def 'Attempt Sync models for a cm handle with existing schema set (#exception).'() {
         given: 'a cm handle to be synced'
-            def yangModelCmHandle = createAdvisedCmHandle('duplicateTag')
-        and: 'The module set tag already exists in the processing semaphore set'
-            mockModuleSetTagsBeingProcessed.add('duplicate-processing-tag') > false
+            def yangModelCmHandle = createAdvisedCmHandle('existing tag')
+        and: 'dmi returns no new yang resources'
+            mockDmiModelOperations.getNewYangResourcesFromDmi(*_) >> [:]
+        and: 'already defined exception occurs when creating schema (existing)'
+            mockCpsModuleService.createSchemaSetFromModules(*_) >> { throw exception  }
         when: 'module sync is triggered'
             objectUnderTest.syncAndCreateSchemaSetAndAnchor(yangModelCmHandle)
-        then: 'a ncmp exception is thrown with the relevant details'
-            def exceptionThrown = thrown(NcmpException)
-            assert exceptionThrown.message.contains('duplicateTag')
-            assert exceptionThrown.details.contains('duplicateTag')
-            assert exceptionThrown.details.contains('ch-1')
+        then: 'no exception is thrown up'
+            noExceptionThrown()
+        where: 'following exceptions occur'
+            exception << [ AlreadyDefinedException.forSchemaSet('', '', null),
+                           new DuplicatedYangResourceException('', '', null) ]
     }
 
-    def 'Upgrade model for an existing cm handle with Module Set Tag where the modules are #scenario'() {
-        given: 'a cm handle being upgraded to module set tag: tag-1'
+    def 'Model upgrade without using Module Set Tags (legacy) where the modules are in database.'() {
+        given: 'a cm handle being upgraded without using module set tags'
             def ncmpServiceCmHandle = new NcmpServiceCmHandle()
-            ncmpServiceCmHandle.setCompositeState(new CompositeStateBuilder().withLockReason(MODULE_UPGRADE, 'Upgrade to ModuleSetTag: tag-1').build())
+            ncmpServiceCmHandle.setCompositeState(new CompositeStateBuilder().withLockReason(MODULE_UPGRADE, '').build())
             def dmiServiceName = 'some service name'
             ncmpServiceCmHandle.cmHandleId = 'upgraded-ch'
-            def yangModelCmHandle = YangModelCmHandle.toYangModelCmHandle(dmiServiceName, '', '', ncmpServiceCmHandle,'tag-1', '', '')
-        and: 'some module references'
-            def moduleReferences =  [ new ModuleReference('module1','1') ]
+            def yangModelCmHandle = YangModelCmHandle.toYangModelCmHandle(dmiServiceName, '', '', ncmpServiceCmHandle,'', '', '')
         and: 'DMI operations returns some module references for upgraded cm handle'
+            def moduleReferences =  [ new ModuleReference('module1','1') ]
             mockDmiModelOperations.getModuleReferences(yangModelCmHandle) >> moduleReferences
             mockDmiModelOperations.getNewYangResourcesFromDmi(_, []) >> [:]
-        and: 'none of these module references are new (unknown to the system)'
+        and: 'none of these module references are new (all already known to the system)'
             mockCpsModuleService.identifyNewModuleReferences(_) >> []
-        and: 'CPS-Core returns list of existing module resources for TBD'
-            mockCpsModuleService.getYangResourcesModuleReferences(*_) >> [ new ModuleReference('module1','1') ]
-        and: 'the service returns a list of module references when queried with the specified attributes'
-            mockCpsModuleService.getModuleReferencesByAttribute(*_) >> existingModuleReferences
-        and: 'the other cm handle is a state ready'
-            mockCmHandleQueries.cmHandleHasState('otherId', CmHandleState.READY) >> true
         when: 'module sync is triggered'
             objectUnderTest.syncAndUpgradeSchemaSet(yangModelCmHandle)
         then: 'update schema set from module is invoked for the upgraded cm handle'
             1 * mockCpsModuleService.upgradeSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'upgraded-ch', [:], moduleReferences)
-        and: 'create schema set from module is not invoked for the upgraded cm handle'
-            0 * mockCpsModuleService.createSchemaSetFromModules(*_)
         and: 'No anchor is created for the upgraded cm handle'
             0 * mockCpsAnchorService.createAnchor(*_)
-        where: 'the following parameters are used'
-            scenario      | existingModuleReferences
-            'new'         | []
-            'in database' | [new ModuleReference('module1', '1')]
     }
 
-    def 'upgrade model for an existing cm handle'() {
+    def 'Model upgrade using to existing Module Set Tag'() {
         given: 'a cm handle that is ready but locked for upgrade'
             def ncmpServiceCmHandle = new NcmpServiceCmHandle()
-            ncmpServiceCmHandle.setCompositeState(new CompositeStateBuilder()
-                .withLockReason(MODULE_UPGRADE, 'Upgrade to ModuleSetTag: targetModuleSetTag').build())
+            ncmpServiceCmHandle.setCompositeState(new CompositeStateBuilder().withLockReason(MODULE_UPGRADE, 'Upgrade to ModuleSetTag: ' + tagTo).build())
             ncmpServiceCmHandle.setCmHandleId('cmHandleId-1')
-            def yangModelCmHandle = YangModelCmHandle.toYangModelCmHandle('some service name', '', '', ncmpServiceCmHandle, 'targetModuleSetTag', '', '')
+            def yangModelCmHandle = YangModelCmHandle.toYangModelCmHandle('some service name', '', '', ncmpServiceCmHandle, tagFrom, '', '')
             mockCmHandleQueries.cmHandleHasState('cmHandleId-1', CmHandleState.READY) >> true
-        and: 'the module service returns some module references'
-            def moduleReferences = [new ModuleReference('module1', '1'), new ModuleReference('module2', '2')]
-            mockCpsModuleService.getYangResourcesModuleReferences(*_)>> moduleReferences
-        and: 'the service returns a list of module references when queried with the specified attributes'
-            mockCpsModuleService.getModuleReferencesByAttribute(*_) >> moduleReferences
+        and: 'the module tag (schemaset) exists is #schemaExists'
+            mockCpsModuleService.schemaSetExists(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, tagTo) >> schemaExists
+        and: 'DMI operations returns some module references for upgraded cm handle'
+            def moduleReferences =  [ new ModuleReference('module1','1') ]
+            expectedCallsToDmi * mockDmiModelOperations.getModuleReferences(yangModelCmHandle) >> moduleReferences
+        and: 'dmi returns no new yang resources'
+            mockDmiModelOperations.getNewYangResourcesFromDmi(*_) >> [:]
+        and: 'none of these module references are new (all already known to the system)'
+            expectedCallsToModuleService * mockCpsModuleService.identifyNewModuleReferences(_) >> []
         when: 'module upgrade is triggered'
             objectUnderTest.syncAndUpgradeSchemaSet(yangModelCmHandle)
-        then: 'the upgrade is delegated to the module service (with the correct parameters)'
-            1 * mockCpsModuleService.upgradeSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'cmHandleId-1', Collections.emptyMap(), moduleReferences)
-    }
-
-    def 'Delete Schema Set for CmHandle'() {
-        when: 'delete schema set if exists is called'
-            objectUnderTest.deleteSchemaSetIfExists('some-cmhandle-id')
-        then: 'the module service is invoked to delete the correct schema set'
-            1 * mockCpsModuleService.deleteSchemaSet(expectedDataspaceName, 'some-cmhandle-id', CascadeDeleteAllowed.CASCADE_DELETE_ALLOWED)
-    }
-
-    def 'Delete a non-existing Schema Set for CmHandle' () {
-        given: 'the DB throws an exception because its Schema Set does not exist'
-           mockCpsModuleService.deleteSchemaSet(*_) >> { throw new SchemaSetNotFoundException('some-dataspace-name', 'some-cmhandle-id') }
-        when: 'delete schema set if exists is called'
-            objectUnderTest.deleteSchemaSetIfExists('some-cmhandle-id')
-        then: 'the exception from the DB is ignored; there are no exceptions'
-            noExceptionThrown()
-    }
-
-    def 'Delete Schema Set for CmHandle with other exception' () {
-        given: 'an exception other than SchemaSetNotFoundException is thrown'
-            UnsupportedOperationException unsupportedOperationException = new UnsupportedOperationException();
-            1 * mockCpsModuleService.deleteSchemaSet(*_) >> { throw unsupportedOperationException }
-        when: 'delete schema set if exists is called'
-            objectUnderTest.deleteSchemaSetIfExists('some-cmhandle-id')
-        then: 'an exception is thrown'
-            def result = thrown(UnsupportedOperationException)
-            result == unsupportedOperationException
-    }
-
-    def 'Clear module set cache.'() {
-        given: 'something in the module set cache'
-            objectUnderTest.privateModuleSetCache.put('test',new ModuleDelta([],[:]))
-        when: 'the cache is cleared'
-            objectUnderTest.clearPrivateModuleSetCache()
-        then: 'the cache is empty'
-            objectUnderTest.privateModuleSetCache.isEmpty()
+        then: 'the upgrade is delegated to the anchor service (with the correct parameters) except when new tag is blank'
+            expectedCallsToAnchorService * mockCpsAnchorService.updateAnchorSchemaSet(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, 'cmHandleId-1', tagTo)
+        where: 'with or without from tag'
+            scenario                         | schemaExists | tagFrom  | tagTo  || expectedCallsToDmi | expectedCallsToModuleService | expectedCallsToAnchorService
+            'from no tag to existing tag'    | true         | ''       | 'tagTo'|| 0                  | 0                            | 1
+            'from tag to other existing tag' | true         | 'oldTag' | 'tagTo'|| 0                  | 0                            | 1
+            'to new tag'                     | false        | 'oldTag' | 'tagTo'|| 1                  | 1                            | 1
+            'to NO tag'                      | true         | 'oldTag' | ''     || 1                  | 1                            | 0
     }
 
     def createAdvisedCmHandle(moduleSetTag) {
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasksSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasksSpec.groovy
index 556ed0b63c..92f4b38f31 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasksSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/ModuleSyncTasksSpec.groovy
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  Modifications Copyright (C) 2022 Bell Canada
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
@@ -29,15 +29,16 @@ import com.hazelcast.config.Config
 import com.hazelcast.core.Hazelcast
 import com.hazelcast.instance.impl.HazelcastInstanceFactory
 import com.hazelcast.map.IMap
+import org.onap.cps.api.exceptions.DataNodeNotFoundException
+import org.onap.cps.ncmp.api.inventory.models.CmHandleState
 import org.onap.cps.ncmp.api.inventory.models.CompositeState
 import org.onap.cps.ncmp.api.inventory.models.CompositeStateBuilder
 import org.onap.cps.ncmp.impl.inventory.InventoryPersistence
-import org.onap.cps.ncmp.api.inventory.models.CmHandleState
 import org.onap.cps.ncmp.impl.inventory.models.YangModelCmHandle
 import org.onap.cps.ncmp.impl.inventory.sync.lcm.LcmEventsCmHandleStateHandler
-import org.onap.cps.api.exceptions.DataNodeNotFoundException
 import org.slf4j.LoggerFactory
 import spock.lang.Specification
+
 import java.util.concurrent.atomic.AtomicInteger
 
 import static org.onap.cps.ncmp.api.inventory.models.LockReasonCategory.MODULE_SYNC_FAILED
@@ -87,10 +88,7 @@ class ModuleSyncTasksSpec extends Specification {
             mockInventoryPersistence.getYangModelCmHandle('cm-handle-2') >> cmHandle2
         when: 'module sync poll is executed'
             objectUnderTest.performModuleSync(['cm-handle-1', 'cm-handle-2'], batchCount)
-        then: 'module sync service deletes schemas set of each cm handle if it already exists'
-            1 * mockModuleSyncService.deleteSchemaSetIfExists('cm-handle-1')
-            1 * mockModuleSyncService.deleteSchemaSetIfExists('cm-handle-2')
-        and: 'module sync service is invoked for each cm handle'
+        then: 'module sync service is invoked for each cm handle'
             1 * mockModuleSyncService.syncAndCreateSchemaSetAndAnchor(_) >> { args -> assert args[0].id == 'cm-handle-1' }
             1 * mockModuleSyncService.syncAndCreateSchemaSetAndAnchor(_) >> { args -> assert args[0].id == 'cm-handle-2' }
         and: 'the state handler is called for the both cm handles'
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfigSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfigSpec.groovy
index 3213e5d442..7db9e5a870 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfigSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/inventory/sync/SynchronizationCacheConfigSpec.groovy
@@ -1,6 +1,6 @@
 /*
  * ============LICENSE_START========================================================
- *  Copyright (C) 2022-2024 Nordix Foundation
+ *  Copyright (C) 2022-2025 Nordix Foundation
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -20,7 +20,6 @@
 
 package org.onap.cps.ncmp.impl.inventory.sync
 
-import com.hazelcast.collection.ISet
 import com.hazelcast.config.Config
 import com.hazelcast.core.Hazelcast
 import com.hazelcast.map.IMap
@@ -45,9 +44,6 @@ class SynchronizationCacheConfigSpec extends Specification {
     @Autowired
     IMap<String, Boolean> dataSyncSemaphores
 
-    @Autowired
-    ISet<String> moduleSetTagsBeingProcessed
-
     def cleanupSpec() {
         Hazelcast.getHazelcastInstanceByName('cps-and-ncmp-hazelcast-instance-test-config').shutdown()
     }
@@ -59,8 +55,6 @@ class SynchronizationCacheConfigSpec extends Specification {
             assert null != moduleSyncStartedOnCmHandles
         and: 'system is able to create an instance of a map to hold data sync semaphores'
             assert null != dataSyncSemaphores
-        and: 'system is able to create an instance of a set to hold module set tags being processed'
-            assert null != moduleSetTagsBeingProcessed
         and: 'there is only one instance with the correct name'
             assert Hazelcast.allHazelcastInstances.size() == 1
             assert Hazelcast.allHazelcastInstances.name[0] == 'cps-and-ncmp-hazelcast-instance-test-config'