# Unable to create snapshots with cifs share 9.4.0 **URL:** \ **Category:** Elasticsearch\ **Tags:** snapshot-and-restore\ **Created:** [May 11, 2026, 9:37am UTC](https://discuss.elastic.co/t/unable-to-create-snapshots-with-cifs-share-9-4-0/386271 "2026-05-11T09:37:51Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![expErg](https://avatars.discourse-cdn.com/v4/letter/e/c68b51/32.png) [@expErg](https://discuss.elastic.co/u/expErg)\ **Post date:** [May 11, 2026, 9:37am UTC](https://discuss.elastic.co/t/unable-to-create-snapshots-with-cifs-share-9-4-0/386271/1 "2026-05-11T09:37:51Z")
Hello, Since upgrading to 9.4.0, we are experiencing snapshot failures on our CIFS-mounted shared repository. **Timeline:** - Last successful snapshot: May 6, before the upgrade - Upgrade to 9.4.0 performed: May 6 at 12:00 PM Europe/Paris - All snapshot attempts have failed since then **Repository configuration:** json ```auto { "elasticsearch": { "type": "fs", "uuid": "46diYBCrQLqmDchEbLpwVQ", "settings": { "location": "/svg/backup" } } } ``` `/svg/backup` is a CIFS mount present on all Elasticsearch nodes, and `path.repo` is defined in `elasticsearch.yml` on each node. Snapshot failed log ```auto { "type": "snapshot_exception", "reason": "[elasticsearch:2026.05.11-daily-snapshot-elasticsearch-lk-qkzvyshglta6cz0xjig/tq5pklx9TkepDZ-HdphGLA] failed to update snapshot in repository", "caused_by": { "type": "file_system_exception", "reason": "/svg/backup/index-2453 -> /svg/backup/pending-index-2453-KXOuCfGoQvaWU-SI_n_pHw: Opération non supportée" } } ``` **Comments** Creating/moving files in the share from elastic host with elasticsearch user work. Creating hardlink don't. I don't know the way elastic performed snapshot before 9.4.0, but it seems to use hardlink now. Which is not _well_ supported in CIFS. I didn't see any informations about snapshots in breaking change section of the release note. **Questions:** - Is this an intentional change or a regression? **Logs:** Repository verification: ```auto org.elasticsearch.repositories.RepositoryVerificationException: [elasticsearch] path is not accessible on master node Caused by: java.nio.file.FileSystemException: /svg/backup/tests-mXWL-4lfTNKJI-PdsCUdxw/master.dat -> /svg/backup/tests-mXWL-4lfTNKJI-PdsCUdxw/pending-master.dat-bg4uXHJSQ4GOLBDkKhswvA: Opération non supportée at java.base/sun.nio.fs.UnixException.translateToIOException(UnixException.java:102) at java.base/sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:108) at java.base/sun.nio.fs.UnixFileSystemProvider.createLink(UnixFileSystemProvider.java:528) at java.base/java.nio.file.Files.createLink(Files.java:1020) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.blobstore.fs.FsBlobContainer.moveAtomicallyUsingHardLink(FsBlobContainer.java:430) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.blobstore.fs.FsBlobContainer.moveBlobAtomic(FsBlobContainer.java:408) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.blobstore.fs.FsBlobContainer.writeBlobAtomic(FsBlobContainer.java:343) at org.elasticsearch.server@9.4.0/org.elasticsearch.repositories.blobstore.BlobStoreRepository.startVerification(BlobStoreRepository.java:2477) at org.elasticsearch.server@9.4.0/org.elasticsearch.repositories.RepositoriesService$4.doRun(RepositoriesService.java:697) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:1114) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:27) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614) at java.base/java.lang.Thread.run(Thread.java:1516) ``` Snapshot failed logs: ```auto failed to create snapshot for snapshot lifecycle policy [daily-snapshot]", "ecs.version": "1.2.0","service.name":"ES_ECS","event.dataset":"elasticsearch.server","process.thread.name":"elasticsearch[LXELK01][masterService#updateTask][T#1427]","log.logger":"org.elasticsearch.xpack.slm.SnapshotLifecycleTask","trace.id":"bbeb59e48798085598552b3022b697b8","elasticsearch.cluster.uuid":"z0kseJw_QUu8UQMoRXNsmg","elasticsearch.node.id":"fj8fXLCSQOWEYhQ4Qpwa2Q","elasticsearch.node.name":"LXELK01","elasticsearch.cluster.name":"es-cluster","error.type":"org.elasticsearch.snapshots.SnapshotException","error.message":"[elasticsearch:2026.05.11-daily-snapshot-elasticsearch-lk-qkzvyshglta6cz0xjig/tq5pklx9TkepDZ-HdphGLA] failed to update snapshot in repository","error.stack_trace":"org.elasticsearch.snapshots.SnapshotException: [elasticsearch:2026.05.11-daily-snapshot-elasticsearch-lk-qkzvyshglta6cz0xjig/tq5pklx9TkepDZ-HdphGLA] failed to update snapshot in repository at org.elasticsearch.server@9.4.0/org.elasticsearch.repositories.blobstore.BlobStoreRepository.lambda$finalizeSnapshot$31(BlobStoreRepository.java:2089) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations$DelegatingResponseActionListener.acceptException(ActionListenerImplementations.java:202) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeAcceptException(ActionListenerImplementations.java:78) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations$DelegatingResponseActionListener.onFailure(ActionListenerImplementations.java:207) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener$FailureResult.complete(SubscribableListener.java:448) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.tryComplete(SubscribableListener.java:351) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.setResult(SubscribableListener.java:376) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.onFailure(SubscribableListener.java:288) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeAcceptException(ActionListenerImplementations.java:78) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeOnFailure(ActionListenerImplementations.java:89) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.DelegatingActionListener.onFailure(DelegatingActionListener.java:32) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener$FailureResult.complete(SubscribableListener.java:448) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.tryComplete(SubscribableListener.java:351) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.setResult(SubscribableListener.java:376) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.onFailure(SubscribableListener.java:288) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeAcceptException(ActionListenerImplementations.java:78) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeOnFailure(ActionListenerImplementations.java:89) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.DelegatingActionListener.onFailure(DelegatingActionListener.java:32) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeAcceptException(ActionListenerImplementations.java:78) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations.safeOnFailure(ActionListenerImplementations.java:89) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.DelegatingActionListener.onFailure(DelegatingActionListener.java:32) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations$ResponseWrappingActionListener.onResponse(ActionListenerImplementations.java:263) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener$SuccessResult.complete(SubscribableListener.java:436) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.tryComplete(SubscribableListener.java:347) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.setResult(SubscribableListener.java:376) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.support.SubscribableListener.onResponse(SubscribableListener.java:283) at org.elasticsearch.server@9.4.0/org.elasticsearch.repositories.blobstore.BlobStoreRepository.lambda$writeIndexGen$47(BlobStoreRepository.java:3123) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionRunnable$4.doRun(ActionRunnable.java:101) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:1114) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:27) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614) at java.base/java.lang.Thread.run(Thread.java:1516) Caused by: java.nio.file.FileSystemException: /svg/backup/index-2453 -> /svg/backup/pending-index-2453-KXOuCfGoQvaWU-SI_n_pHw: Opération non supportée at java.base/sun.nio.fs.UnixException.translateToIOException(UnixException.java:102) at java.base/sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:108) at java.base/sun.nio.fs.UnixFileSystemProvider.createLink(UnixFileSystemProvider.java:528) at java.base/java.nio.file.Files.createLink(Files.java:1020) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.blobstore.fs.FsBlobContainer.moveAtomicallyUsingHardLink(FsBlobContainer.java:430) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.blobstore.fs.FsBlobContainer.moveBlobAtomic(FsBlobContainer.java:408) at org.elasticsearch.server@9.4.0/org.elasticsearch.common.blobstore.fs.FsBlobContainer.writeMetadataBlob(FsBlobContainer.java:271) at org.elasticsearch.server@9.4.0/org.elasticsearch.repositories.blobstore.BlobStoreRepository.writeAtomic(BlobStoreRepository.java:3462) at org.elasticsearch.server@9.4.0/org.elasticsearch.repositories.blobstore.BlobStoreRepository.lambda$writeIndexGen$50(BlobStoreRepository.java:3146) at org.elasticsearch.server@9.4.0/org.elasticsearch.action.ActionListenerImplementations$ResponseWrappingActionListener.onResponse(ActionListenerImplementations.java:261) ... 11 more ``` Edit 11/05/2026 15:13: I tried with es-start-local version 9.3.3. And snapshot works without issues with es-start-local version 9.4.0, we experiencing same issue described above. ---
**Author:** ![michalborek](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/michalborek/32/147528_2.png) [@michalborek](https://discuss.elastic.co/u/michalborek)\ **Post date:** [May 11, 2026, 4:00pm UTC](https://discuss.elastic.co/t/unable-to-create-snapshots-with-cifs-share-9-4-0/386271/2 "2026-05-11T16:00:01Z")
Thank you @expErg for sharing this. The hard link approach for moving files has recently been introduced to Elasticsearch to solve a problem of a race condition in this area. There is a fallback for non-compliant systems, but apparently a different exception than anticipated is thrown there (we catch `UnsupportedOperationException`, as defined in `java.nio.file.Files#createLink` but it looks like the the `UnixFileSystemProvider` throws a different one). ---
**Author:** ![expErg](https://avatars.discourse-cdn.com/v4/letter/e/c68b51/32.png) [@expErg](https://discuss.elastic.co/u/expErg)\ **Post date:** [May 12, 2026, 6:58am UTC](https://discuss.elastic.co/t/unable-to-create-snapshots-with-cifs-share-9-4-0/386271/3 "2026-05-12T06:58:52Z")
Thank you @michalborek for the valuable information. After a little more research, I was able to find the PR that introduced this behavior. Should I open an issue on GitHub to track this ? ---
**Author:** ![michalborek](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/michalborek/32/147528_2.png) [@michalborek](https://discuss.elastic.co/u/michalborek)\ **Post date:** [May 12, 2026, 7:11am UTC](https://discuss.elastic.co/t/unable-to-create-snapshots-with-cifs-share-9-4-0/386271/4 "2026-05-12T07:11:28Z")
If you open an issue, I can link it with my PR (we'd have your installation details that may help in future cases). I proposed a PR with the fix here: [Fix FsBlobContainer.moveBlobAtomic fallback on CIFS filesystems by michalborek · Pull Request #148777 · elastic/elasticsearch · GitHub](https://github.com/elastic/elasticsearch/pull/148777) . ---
**Author:** ![expErg](https://avatars.discourse-cdn.com/v4/letter/e/c68b51/32.png) [@expErg](https://discuss.elastic.co/u/expErg)\ **Post date:** [May 12, 2026, 7:19am UTC](https://discuss.elastic.co/t/unable-to-create-snapshots-with-cifs-share-9-4-0/386271/5 "2026-05-12T07:19:04Z")
[The issue](https://github.com/elastic/elasticsearch/issues/148811). Thank you for the quick response!