# Any efficient way to perform shards reduction of the original index? Need to do shards rebalancing after shards reduction?
**URL:** https://discuss.elastic.co/t/any-efficient-way-to-perform-shards-reduction-of-the-original-index-need-to-do-shards-rebalancing-after-shards-reduction/266574
**Category:** Elasticsearch
**Created:** [March 8, 2021, 3:08pm UTC](https://discuss.elastic.co/t/any-efficient-way-to-perform-shards-reduction-of-the-original-index-need-to-do-shards-rebalancing-after-shards-reduction/266574 "2021-03-08T15:08:33Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@qub123](https://discuss.elastic.co/u/qub123)
#### Post date: [March 8, 2021, 3:08pm UTC](https://discuss.elastic.co/t/any-efficient-way-to-perform-shards-reduction-of-the-original-index-need-to-do-shards-rebalancing-after-shards-reduction/266574/1 "2021-03-08T15:08:33Z")
Hi, we are trying to reduce number of primary shards, from 5 shards and one replica shard of each primary, to 2 primary shards and one replica of each primary shard.
The process we are going to do as follow. Wondering if we have easier way to do it?
- Reindex the original index (original - 5primary shards, 1 replica for each primaryu) to a new index with “\_new” at the back. (original\_new – 2 primary shards, 1 replica for each primary )
- Delete the original index
- Reindex the ”original\_new” back to “original” index
- Delete the original index
We have 8 nodes in our cluster, I am wondering do we still need to perform shard rebalancing in the cluster, so all the shards can spread evenly. We already have **cluster.routing.allocation.enable all** set in our cluster.
Also what is the different between **cluster.routing.allocation.enable** and **cluster.routing.rebalance.enable**. I am not able to tell the detail different between these two?
**cluster.routing.allocation.enable**
([Dynamic](https://www.elastic.co/guide/en/elasticsearch/reference/7.x/settings.html#dynamic-cluster-setting)) Enable or disable allocation for specific kinds of shards:
all - (default) Allows shard allocation for all kinds of shards.
**cluster.routing.rebalance.enable**
([Dynamic](https://www.elastic.co/guide/en/elasticsearch/reference/7.x/settings.html#dynamic-cluster-setting)) Enable or disable rebalancing for specific kinds of shards:
all - (default) Allows shard balancing for all kinds of shards.
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### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [April 5, 2021, 3:09pm UTC](https://discuss.elastic.co/t/any-efficient-way-to-perform-shards-reduction-of-the-original-index-need-to-do-shards-rebalancing-after-shards-reduction/266574/2 "2021-04-05T15:09:01Z")
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