Do not mark verified from ILM shrink.

server/src/main/java/org/elasticsearch/action/admin/indices/readonly/AddIndexBlockClusterStateUpdateRequest.java

@@ -21,7 +21,7 @@ public record AddIndexBlockClusterStateUpdateRequest(
     TimeValue masterNodeTimeout,
     TimeValue ackTimeout,
     APIBlock block,
-    long taskId,
+    boolean markVerified, long taskId,
     Index[] indices
 ) {
     public AddIndexBlockClusterStateUpdateRequest {

server/src/main/java/org/elasticsearch/action/admin/indices/readonly/AddIndexBlockRequest.java

@@ -9,6 +9,7 @@
 
 package org.elasticsearch.action.admin.indices.readonly;
 
+import org.elasticsearch.TransportVersions;
 import org.elasticsearch.action.ActionRequestValidationException;
 import org.elasticsearch.action.IndicesRequest;
 import org.elasticsearch.action.support.IndicesOptions;
@@ -32,12 +33,18 @@ public class AddIndexBlockRequest extends AcknowledgedRequest<AddIndexBlockReque
     private final APIBlock block;
     private String[] indices;
     private IndicesOptions indicesOptions = IndicesOptions.strictExpandOpen();
+    private boolean markVerified = true;
 
     public AddIndexBlockRequest(StreamInput in) throws IOException {
         super(in);
         indices = in.readStringArray();
         indicesOptions = IndicesOptions.readIndicesOptions(in);
         block = APIBlock.readFrom(in);
+        if (in.getTransportVersion().onOrAfter(TransportVersions.ADD_INDEX_BLOCK_TWO_PHASE)) {
+            markVerified = in.readBoolean();
+        } else {
+            markVerified = false;
+        }
     }
 
     /**
@@ -103,6 +110,14 @@ public AddIndexBlockRequest indicesOptions(IndicesOptions indicesOptions) {
         return this;
     }
 
+    public boolean markVerified() {
+        return markVerified;
+    }
+
+    public AddIndexBlockRequest markVerified(boolean markVerified)  {
+        this.markVerified = markVerified;
+        return this;
+    }
     /**
      * Returns the block to be added
      */
@@ -116,6 +131,9 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeStringArray(indices);
         indicesOptions.writeIndicesOptions(out);
         block.writeTo(out);
+        if (out.getTransportVersion().onOrAfter(TransportVersions.ADD_INDEX_BLOCK_TWO_PHASE)) {
+            out.writeBoolean(markVerified);
+        }
     }
 
     @Override
@@ -136,4 +154,5 @@ public int hashCode() {
         result = 31 * result + Arrays.hashCode(indices);
         return result;
     }
+
 }

server/src/main/java/org/elasticsearch/action/admin/indices/readonly/TransportAddIndexBlockAction.java

@@ -107,6 +107,7 @@ protected void masterOperation(
                 request.masterNodeTimeout(),
                 request.ackTimeout(),
                 request.getBlock(),
+                request.markVerified(),
                 task.getId(),
                 concreteIndices
             ),

server/src/main/java/org/elasticsearch/cluster/metadata/MetadataIndexStateService.java

@@ -513,7 +513,7 @@ public void taskSucceeded(AddBlocksTask task, Map<Index, ClusterBlock> blockedIn
                                             task.request,
                                             blockedIndices,
                                             verifyResults,
-                                            clusterService.state()
+                                            task.request().markVerified() && clusterService.state()
                                                 .getMinTransportVersion()
                                                 .onOrAfter(TransportVersions.ADD_INDEX_BLOCK_TWO_PHASE),
                                             delegate2
@@ -546,7 +546,7 @@ public Tuple<ClusterState, List<AddBlockResult>> executeTask(FinalizeBlocksTask
                 task.blockedIndices,
                 task.verifyResults,
                 task.request.block(),
-                task.flushed()
+                task.markVerified()
             );
             assert finalizeResult.v2().size() == task.verifyResults.size();
             return finalizeResult;
@@ -563,7 +563,7 @@ private record FinalizeBlocksTask(
         AddIndexBlockClusterStateUpdateRequest request,
         Map<Index, ClusterBlock> blockedIndices,
         Map<Index, AddBlockResult> verifyResults,
-        boolean flushed,
+        boolean markVerified,
         ActionListener<AddIndexBlockResponse> listener
     ) implements ClusterStateTaskListener {
         @Override
@@ -983,15 +983,15 @@ private void onlyOpenIndices(final OpenIndexClusterStateUpdateRequest request, f
      * @param blockedIndices the indices and their temporary UUID-based blocks to convert
      * @param verifyResult the index-level results for adding the block
      * @param block the full block to convert to
-     * @param flushed if we are guaranteed that data has been flushed in case of a write-level block.
+     * @param markVerified if the index should be marked verified in case of a write-level block.
      * @return the updated cluster state, as well as the (failed and successful) index-level results for adding the block
      */
     private static Tuple<ClusterState, List<AddBlockResult>> finalizeBlock(
         final ClusterState currentState,
         final Map<Index, ClusterBlock> blockedIndices,
         final Map<Index, AddBlockResult> verifyResult,
         final APIBlock block,
-        final boolean flushed
+        final boolean markVerified
     ) {
         final ClusterBlocks.Builder blocks = ClusterBlocks.builder(currentState.blocks());
         final Metadata.Builder metadata = Metadata.builder(currentState.metadata());
@@ -1043,7 +1043,7 @@ private static Tuple<ClusterState, List<AddBlockResult>> finalizeBlock(
                 logger.debug("add block {} to index {} succeeded", block.block, index);
                 effectivelyBlockedIndices.add(index.getName());
 
-                if (block.getBlock().contains(ClusterBlockLevel.WRITE) && flushed) {
+                if (block.getBlock().contains(ClusterBlockLevel.WRITE) && markVerified) {
                     final IndexMetadata indexMetadata = metadata.getSafe(index);
                     final IndexMetadata.Builder updatedMetadata = IndexMetadata.builder(indexMetadata).state(IndexMetadata.State.CLOSE);
                     metadata.put(

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/DownsampleAction.java

@@ -203,7 +203,7 @@ public List<Step> toSteps(Client client, String phase, StepKey nextStepKey) {
             Instant::now
         );
         // Mark source index as read-only
-        ReadOnlyStep readOnlyStep = new ReadOnlyStep(readOnlyKey, generateDownsampleIndexNameKey, client);
+        ReadOnlyStep readOnlyStep = new ReadOnlyStep(readOnlyKey, generateDownsampleIndexNameKey, client, true);
 
         // Before the downsample action was retry-able, we used to generate a unique downsample index name and delete the previous index in
         // case a failure occurred. The downsample action can now retry execution in case of failure and start where it left off, so no

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/ReadOnlyAction.java

@@ -69,7 +69,7 @@ public List<Step> toSteps(Client client, String phase, StepKey nextStepKey) {
             readOnlyKey,
             Instant::now
         );
-        ReadOnlyStep readOnlyStep = new ReadOnlyStep(readOnlyKey, nextStepKey, client);
+        ReadOnlyStep readOnlyStep = new ReadOnlyStep(readOnlyKey, nextStepKey, client, true);
         return List.of(checkNotWriteIndexStep, waitUntilTimeSeriesEndTimeStep, readOnlyStep);
     }
 

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/ReadOnlyStep.java

@@ -23,9 +23,15 @@
  */
 public class ReadOnlyStep extends AsyncActionStep {
     public static final String NAME = "readonly";
+    private final boolean markVerified;
 
-    public ReadOnlyStep(StepKey key, StepKey nextStepKey, Client client) {
+    /**
+     * @param markVerified whether the index should be marked verified after becoming read-only, ensuring that N-2 is supported without
+     *                     manual intervention. Should be set to true when the read-only block is not temporary.
+     */
+    public ReadOnlyStep(StepKey key, StepKey nextStepKey, Client client, boolean markVerified) {
         super(key, nextStepKey, client);
+        this.markVerified = markVerified;
     }
 
     @Override
@@ -39,7 +45,8 @@ public void performAction(
             .indices()
             .execute(
                 TransportAddIndexBlockAction.TYPE,
-                new AddIndexBlockRequest(WRITE, indexMetadata.getIndex().getName()).masterNodeTimeout(TimeValue.MAX_VALUE),
+                new AddIndexBlockRequest(WRITE, indexMetadata.getIndex().getName()).masterNodeTimeout(TimeValue.MAX_VALUE)
+                    .markVerified(markVerified),
                 listener.delegateFailureAndWrap((l, response) -> {
                     if (response.isAcknowledged() == false) {
                         throw new ElasticsearchException("read only add block index request failed to be acknowledged");

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/ShrinkAction.java

@@ -233,7 +233,7 @@ public List<Step> toSteps(Client client, String phase, Step.StepKey nextStepKey)
             readOnlyKey,
             Instant::now
         );
-        ReadOnlyStep readOnlyStep = new ReadOnlyStep(readOnlyKey, checkTargetShardsCountKey, client);
+        ReadOnlyStep readOnlyStep = new ReadOnlyStep(readOnlyKey, checkTargetShardsCountKey, client, false);
         CheckTargetShardsCountStep checkTargetShardsCountStep = new CheckTargetShardsCountStep(
             checkTargetShardsCountKey,
             cleanupShrinkIndexKey,