# How long does it take to clone an index with 2TB of data?

**URL:** <https://discuss.elastic.co/t/how-long-does-it-take-to-clone-an-index-with-2tb-of-data/329969>\
**Category:** Elasticsearch\
**Created:** [April 14, 2023, 6:09am UTC](https://discuss.elastic.co/t/how-long-does-it-take-to-clone-an-index-with-2tb-of-data/329969 "2023-04-14T06:09:50Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![dilshadpaleri](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dilshadpaleri/32/119808_2.png) [@dilshadpaleri](https://discuss.elastic.co/u/dilshadpaleri)\
**Post date:** [April 14, 2023, 6:09am UTC](https://discuss.elastic.co/t/how-long-does-it-take-to-clone-an-index-with-2tb-of-data/329969/1 "2023-04-14T06:09:50Z")

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Hi,  
I want to create an identical copy of an existing index with about 2 TB of data, Clone API seems to be the best option here. To clone an index, the index must be marked as read-only, so it will block my application when the clone operation is performed. Due to some design limitations, I can't use an alias or ILM-managed indexes here, so I'd like to know how long it would take to clone an index with 2TB of data.

Total Node in cluster:6  
Number of primary shards: 10  
Number of replica shards: 1  
Memory per Node: 5GB  
Elasticsearch 7.17

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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:** [April 14, 2023, 7:24am UTC](https://discuss.elastic.co/t/how-long-does-it-take-to-clone-an-index-with-2tb-of-data/329969/2 "2023-04-14T07:24:08Z")

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It's usually fast (a few seconds) because it hard-links the data instead of copying it as long as your filesystem supports hard-links. But even if it takes a little longer to complete, you can remove the read-only block as soon as the clone has started.

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<div class="post-metadata">

**Author:** ![dilshadpaleri](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dilshadpaleri/32/119808_2.png) [@dilshadpaleri](https://discuss.elastic.co/u/dilshadpaleri)\
**Post date:** [April 14, 2023, 7:45am UTC](https://discuss.elastic.co/t/how-long-does-it-take-to-clone-an-index-with-2tb-of-data/329969/3 "2023-04-14T07:45:41Z")

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Thank you David for the quick response.

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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:** [May 12, 2023, 7:46am UTC](https://discuss.elastic.co/t/how-long-does-it-take-to-clone-an-index-with-2tb-of-data/329969/4 "2023-05-12T07:46:19Z")

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