repro #41898

Author: original-brownbear

server/src/main/java/org/elasticsearch/repositories/blobstore/BlobStoreRepository.java

@@ -395,9 +395,6 @@ public void initializeSnapshot(SnapshotId snapshotId, List<IndexId> indices, Met
             if (repositoryData.getAllSnapshotIds().stream().anyMatch(s -> s.getName().equals(snapshotName))) {
                 throw new InvalidSnapshotNameException(metadata.name(), snapshotId.getName(), "snapshot with the same name already exists");
             }
-            if (snapshotFormat.exists(blobContainer(), snapshotId.getUUID())) {
-                throw new InvalidSnapshotNameException(metadata.name(), snapshotId.getName(), "snapshot with the same name already exists");
-            }
 
             // Write Global MetaData
             globalMetaDataFormat.write(clusterMetaData, blobContainer(), snapshotId.getUUID());

server/src/test/java/org/elasticsearch/snapshots/mockstore/MockEventuallyConsistentRepository.java

@@ -172,7 +172,10 @@ public void writeBlob(String blobName, InputStream inputStream, long blobSize, b
                         super.writeBlob(blobName, new ByteArrayInputStream(baos.toByteArray()), blobSize, failIfAlreadyExists);
                         if (cachedMisses.contains(blobName)) {
                             // Remove cached missing blob later to simulate inconsistency between list and get calls.
-                            deterministicTaskQueue.scheduleNow(() -> cachedMisses.remove(blobName));
+                            // Just scheduling at the current time since we get randomized future execution from the deterministic
+                            // task queue's jitter anyway.
+                            deterministicTaskQueue.scheduleAt(
+                                deterministicTaskQueue.getCurrentTimeMillis(), () -> cachedMisses.remove(blobName));
                         }
                     } catch (NoSuchFileException | FileAlreadyExistsException e) {
                         // Ignoring, assuming a previous concurrent delete removed the parent path and that overwrites are not