# Different disk sizes

**URL:** <https://discuss.elastic.co/t/different-disk-sizes/174011>\
**Category:** Elasticsearch\
**Created:** [March 26, 2019, 8:47pm UTC](https://discuss.elastic.co/t/different-disk-sizes/174011 "2019-03-26T20:47:59Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![zeldor](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/zeldor/32/42831_2.png) [@zeldor](https://discuss.elastic.co/u/zeldor)\
**Post date:** [March 26, 2019, 8:47pm UTC](https://discuss.elastic.co/t/different-disk-sizes/174011/1 "2019-03-26T20:47:59Z")

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Hello ES community,

I have a question regarding different disk sizes on data-nodes in a elasticsearch-cluster.  
Let's say I have 8 data nodes and all of then have different disk sizes:  
1: 300GB  
2: 300GB  
3: 300GB  
4: 500GB  
5: 500GB  
6: 500GB  
7: 500GB  
8: 500GB

How Elasticsearch will handle this situation when the nodes with 300GB get the watermark reached?  
Will the cluster be able to use the 500GB disks until the watermark or will they be filled like a 300GB disk?

watermark.low and watermark.high have the default values.

Thanks and BR

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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:** [March 27, 2019, 8:16am UTC](https://discuss.elastic.co/t/different-disk-sizes/174011/2 "2019-03-27T08:16:10Z")

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The disk watermarks are either percentages of the total size of the disk, or else they are an amount of free space. In either case, a larger disk will have more space below each watermark.

However the shard allocator assumes that all nodes are equivalent, so it might make poor allocation decisions if this isn't the case.

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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:** [April 24, 2019, 8:16am UTC](https://discuss.elastic.co/t/different-disk-sizes/174011/3 "2019-04-24T08:16:15Z")

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