fallback to full snapshots for clvm-ng - incremental not supported in 4.23

Author: Pearl Dsilva

plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/storage/KVMStorageProcessor.java

@@ -2132,11 +2132,13 @@ private SnapshotObjectTO takeIncrementalVolumeSnapshotOfStoppedVm(SnapshotObject
                 ObjectUtils.defaultIfNull(secondaryPool, primaryPool));
         try {
             // For CLVM_NG incremental snapshots, validate bitmap before proceeding
+            /*
             SnapshotObjectTO bitmapValidationResult = validateClvmNgBitmapAndFallbackIfNeeded(snapshotObjectTO, primaryPool,
                     secondaryPool, secondaryPoolUrl, snapshotName, volumeObjectTo, conn, wait);
             if (bitmapValidationResult != null) {
                 return bitmapValidationResult;
             }
+             */
 
             String vmName = String.format("DUMMY-VM-%s", snapshotName);
 

server/src/main/java/com/cloud/storage/snapshot/SnapshotManagerImpl.java

@@ -1636,6 +1636,17 @@ public SnapshotInfo takeSnapshot(VolumeInfo volume) throws ResourceAllocationExc
         StoragePoolType poolType = volume.getStoragePoolType();
         boolean isClvmNgIncrementalCandidate = StoragePoolType.CLVM_NG == poolType
                 && kvmIncrementalSnapshot.valueIn(clusterId);
+
+        // CLVM-NG incremental snapshots are not supported in this release.
+        // Warn and fall back to a full snapshot so the job still succeeds.
+        if (isClvmNgIncrementalCandidate) {
+            logger.warn("Incremental snapshots are not supported for CLVM-NG storage pools in this release. " +
+                    "Falling back to a full snapshot for volume [{}]. " +
+                    "Please disable the '{}' setting for CLVM-NG clusters.",
+                    volume.getUuid(), kvmIncrementalSnapshot.key());
+            isClvmNgIncrementalCandidate = false;
+        }
+
         if ((isKvmAndFileBasedStorage || isClvmNgIncrementalCandidate) && backupSnapToSecondary) {
             DataStore imageStore = snapshotSrv.findSnapshotImageStore(snapshot);
             if (imageStore == null) {
@@ -1860,7 +1871,8 @@ private void updateSnapshotPayload(long storagePoolId, CreateSnapshotPayload pay
             payload.setLocationType(null);
         }
 
-        if ((isKvmAndFileBasedStorage || StoragePoolType.CLVM_NG == poolType) && kvmIncrementalSnapshot.valueIn(clusterId)) {
+        // CLVM_NG excluded: incremental snapshots not supported in this release (handled in takeSnapshot).
+        if (isKvmAndFileBasedStorage && kvmIncrementalSnapshot.valueIn(clusterId)) {
             payload.setKvmIncrementalSnapshot(true);
         }
     }