# Elasticsearch Data Recovery

**URL:** <https://discuss.elastic.co/t/elasticsearch-data-recovery/286009>\
**Category:** Elasticsearch\
**Created:** [October 6, 2021, 10:24am UTC](https://discuss.elastic.co/t/elasticsearch-data-recovery/286009 "2021-10-06T10:24:09Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![dawiro](https://avatars.discourse-cdn.com/v4/letter/d/71e660/32.png) [@dawiro](https://discuss.elastic.co/u/dawiro)\
**Post date:** [October 6, 2021, 10:24am UTC](https://discuss.elastic.co/t/elasticsearch-data-recovery/286009/1 "2021-10-06T10:24:09Z")

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Hi,  
We had an incident where all master nodes failed. After they were auto-replaced the old data nodes did not reconnect to the master due to state mismatch. While we were able to clear down the state so the nodes could rejoin the cluster we were not able to recover the index data.

How can we recover index data from data nodes that are effectively joining a new cluster?

Thx  
D

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**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\
**Post date:** [October 11, 2021, 1:07am UTC](https://discuss.elastic.co/t/elasticsearch-data-recovery/286009/2 "2021-10-11T01:07:48Z")

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What version are you using?

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**Author:** ![dawiro](https://avatars.discourse-cdn.com/v4/letter/d/71e660/32.png) [@dawiro](https://discuss.elastic.co/u/dawiro)\
**Post date:** [October 11, 2021, 10:05am UTC](https://discuss.elastic.co/t/elasticsearch-data-recovery/286009/3 "2021-10-11T10:05:23Z")

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Various 7.x releases.

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**Author:** ![DavidTurner](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/davidturner/32/22453_2.png) [@DavidTurner](https://discuss.elastic.co/u/DavidTurner)\
**Post date:** [October 11, 2021, 5:33pm UTC](https://discuss.elastic.co/t/elasticsearch-data-recovery/286009/4 "2021-10-11T17:33:28Z")

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> [@dawiro](#):
>
> How can we recover index data from data nodes that are effectively joining a new cluster?

There's no safe way to do that. The master nodes hold the cluster metadata, without which the data on the data nodes is kinda meaningless. The best way forwards is to restart the failed master nodes, but if you can't do that you should recover your data from a recent snapshot.

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**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [November 8, 2021, 5:34pm UTC](https://discuss.elastic.co/t/elasticsearch-data-recovery/286009/5 "2021-11-08T17:34:28Z")

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