fix(linstor): verify resource deletion completes; warn if stuck in DELETING

plugins/storage/volume/linstor/src/main/java/com/cloud/hypervisor/kvm/storage/LinstorStorageAdaptor.java

@@ -514,6 +514,17 @@ private boolean deRefOrDeleteResource(DevelopersApi api, String rscName, String
                 ApiCallRcList answers = api.resourceDefinitionDelete(rd.getName());
                 checkLinstorAnswersThrow(answers);
                 deleted = true;
+
+                // LINSTOR can return success here while the resource lingers in DELETING state
+                // on the controller (down peer, lost quorum, etc.). Confirm it's actually gone
+                // — if not, log a WARN so operators can clear it manually. Don't throw: the
+                // CloudStack-side accounting has already moved on.
+                if (!LinstorUtil.waitForResourceDefinitionDeleted(api, rd.getName(),
+                        LinstorUtil.DEFAULT_RD_DELETE_VERIFY_TIMEOUT_MILLIS)) {
+                    logger.warn("Linstor: resource {} still present {}ms after delete returned success — " +
+                            "may be stuck in DELETING. Check the LINSTOR controller (linstor resource list).",
+                            rd.getName(), LinstorUtil.DEFAULT_RD_DELETE_VERIFY_TIMEOUT_MILLIS);
+                }
             }
         }
         return deleted;

plugins/storage/volume/linstor/src/main/java/org/apache/cloudstack/storage/datastore/driver/LinstorPrimaryDataStoreDriverImpl.java

@@ -230,6 +230,20 @@ private void deleteResourceDefinition(StoragePoolVO storagePoolVO, String rscDef
                 throw new CloudRuntimeException("Linstor: Unable to delete resource definition: " + rscDefName);
             }
             logger.info("Linstor: Deleted resource {}", rscDefName);
+
+            // LINSTOR can return success on the delete API call while the resource lingers in
+            // DELETING state (peer issues, lost quorum, satellite down). Verify the resource is
+            // actually gone — if not, log a WARN so operators see it. We deliberately do NOT
+            // throw here: the volume is already considered gone on the CloudStack side, and
+            // throwing would leave the CS DB and LINSTOR in different states.
+            if (!LinstorUtil.waitForResourceDefinitionDeleted(linstorApi, rscDefName,
+                    LinstorUtil.DEFAULT_RD_DELETE_VERIFY_TIMEOUT_MILLIS))
+            {
+                logger.warn("Linstor: resource {} still present {}ms after delete returned success — " +
+                        "may be stuck in DELETING. Check the LINSTOR controller (linstor resource list) " +
+                        "and clear manually if the resource has no live peers.",
+                        rscDefName, LinstorUtil.DEFAULT_RD_DELETE_VERIFY_TIMEOUT_MILLIS);
+            }
         } catch (ApiException apiEx)
         {
             logger.error("Linstor: ApiEx - " + apiEx.getMessage());

plugins/storage/volume/linstor/src/main/java/org/apache/cloudstack/storage/datastore/util/LinstorUtil.java

@@ -401,6 +401,57 @@ public static List<ResourceDefinition> getRDListStartingWith(DevelopersApi api,
                 .collect(Collectors.toList());
     }
 
+    /**
+     * Default per-call timeout for {@link #waitForResourceDefinitionDeleted}. Long enough for a
+     * healthy LINSTOR controller to finish a normal delete; short enough not to block the calling
+     * agent thread for too long if the delete is genuinely stuck.
+     */
+    public static final long DEFAULT_RD_DELETE_VERIFY_TIMEOUT_MILLIS = 30_000L;
+
+    /**
+     * Returns {@code true} if the named resource definition is no longer present on the LINSTOR
+     * controller. Used after a {@code resourceDefinitionDelete} to verify the delete actually
+     * completed (LINSTOR can return success on the API call while the resource lingers in
+     * DELETING state due to peer issues, lost quorum, or down satellites).
+     */
+    public static boolean isResourceDefinitionGone(DevelopersApi api, String rscName) throws ApiException {
+        List<ResourceDefinition> all = api.resourceDefinitionList(null, false, null, null, null);
+        if (all == null) {
+            return true;
+        }
+        return all.stream().noneMatch(rd -> rscName.equalsIgnoreCase(rd.getName()));
+    }
+
+    /**
+     * Polls the controller until the named resource definition is gone or the timeout elapses.
+     * Returns {@code true} if the resource was confirmed gone, {@code false} if it was still
+     * present (or the controller kept erroring) at the deadline. Callers should NOT throw on a
+     * {@code false} return — the upstream API call already reported success and the operator
+     * may need to investigate manually. Log a WARN with the resource name instead.
+     */
+    public static boolean waitForResourceDefinitionDeleted(DevelopersApi api, String rscName, long timeoutMillis) {
+        final long deadline = System.currentTimeMillis() + timeoutMillis;
+        while (true) {
+            try {
+                if (isResourceDefinitionGone(api, rscName)) {
+                    return true;
+                }
+            } catch (ApiException e) {
+                LOGGER.debug("LINSTOR delete-verify poll failed for {}: {}", rscName, e.getMessage());
+                // Keep polling — controller may be transiently unavailable.
+            }
+            if (System.currentTimeMillis() >= deadline) {
+                return false;
+            }
+            try {
+                Thread.sleep(1_000L);
+            } catch (InterruptedException ie) {
+                Thread.currentThread().interrupt();
+                return false;
+            }
+        }
+    }
+
     /**
      * Returns a pair list of resource-definitions with ther 1:1 mapped resource-group objects that start with the
      * resource name `startWith`