# Downgrade from 7.9 to 7.8

**URL:** <https://discuss.elastic.co/t/downgrade-from-7-9-to-7-8/255672>\
**Category:** Elasticsearch\
**Created:** [November 17, 2020, 11:15am UTC](https://discuss.elastic.co/t/downgrade-from-7-9-to-7-8/255672 "2020-11-17T11:15:06Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![amralieg](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/amralieg/32/49943_2.png) [@amralieg](https://discuss.elastic.co/u/amralieg)\
**Post date:** [November 17, 2020, 11:15am UTC](https://discuss.elastic.co/t/downgrade-from-7-9-to-7-8/255672/1 "2020-11-17T11:15:06Z")

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Hi All, need some thoughts on this. for some reasons I need to move from v7.9.3 to v7.8. I know I can not do a snapshot and restore. but what are my other options here?  
I thought for reindex from the old cluster to the new cluster, but could not find a bulk reindex API. is there any other more efficient way?

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**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\
**Post date:** [November 17, 2020, 1:09pm UTC](https://discuss.elastic.co/t/downgrade-from-7-9-to-7-8/255672/2 "2020-11-17T13:09:58Z")

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You can not downgrade so you will have to reindex indeed.

> [@amralieg](#):
>
> but could not find a bulk reindex API

What do you mean? The reindex API uses the bulk API behind the scene.  
Do you mean doing all that automatically?

You need to write a script which:

- List all indices from the old cluster: `GET /_cat/indices?h=index`
- For each index, fetch settings, mappings, aliases: `GET INDEX`
- Create the same index in the new cluster (using settings, mappings...): `PUT INDEX`
- Run [Reindex from remote](https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-reindex.html#reindex-from-remote) in the new cluster to reindex from the old cluster

Not sure if there is already a tool which does all that.

Out of curiosity, why would you downgrade?

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<div class="post-metadata">

**Author:** ![amralieg](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/amralieg/32/49943_2.png) [@amralieg](https://discuss.elastic.co/u/amralieg)\
**Post date:** [November 17, 2020, 1:55pm UTC](https://discuss.elastic.co/t/downgrade-from-7-9-to-7-8/255672/3 "2020-11-17T13:55:57Z")

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I mean is there a reindex that do that, and for bulk indexes, so al I do I specify list of indexes and target server and it does the job?

Customer upgraded too soon to 7.9 without realising that we have a migration from GCP to AWS coming.

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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:** [December 15, 2020, 1:56pm UTC](https://discuss.elastic.co/t/downgrade-from-7-9-to-7-8/255672/4 "2020-12-15T13:56:04Z")

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