# ECK 8.17.3 can't set replication factor on system indices

**URL:** https://discuss.elastic.co/t/eck-8-17-3-cant-set-replication-factor-on-system-indices/379697
**Category:** Elasticsearch
**Created:** [July 2, 2025, 7:10am UTC](https://discuss.elastic.co/t/eck-8-17-3-cant-set-replication-factor-on-system-indices/379697 "2025-07-02T07:10:06Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![DanielR1](https://avatars.discourse-cdn.com/v4/letter/d/54ee81/32.png) [@DanielR1](https://discuss.elastic.co/u/DanielR1)
#### Post date: [July 2, 2025, 7:10am UTC](https://discuss.elastic.co/t/eck-8-17-3-cant-set-replication-factor-on-system-indices/379697/1 "2025-07-02T07:10:06Z")

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Hello!

I have deployed a cluster v 8.17.3 using the eck operator, I see all the indices have a replication factor of 0 by default. I have tried to change that using the  
PUT /.internal.alerts-default.alerts-default-000001/\_settings  
{  
"index": {  
"number\_of\_replicas": 1  
}  
}  
but it doesnt take effect, all .internal.alerts keep having a 0 repl factor. Is this how it suppose to be? If on node goes down this could easily bring the cluster in a red state.  
Thanks!

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<div class="post-metadata">

### Author: ![Tortoise](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/tortoise/32/147587_2.png) [@Tortoise](https://discuss.elastic.co/u/Tortoise)
#### Post date: [July 4, 2025, 6:52am UTC](https://discuss.elastic.co/t/eck-8-17-3-cant-set-replication-factor-on-system-indices/379697/2 "2025-07-04T06:52:44Z")

</div>

Hello @DanielR1

Could you please share the output of below :

`GET /_cat/allocation?v&h=disk.percent,node,node.role`

As i can see in the env replicas is already set to 1 for this system index & auto\_expand\_replicas is 0 or 1.

```auto
"number_of_shards": "1",
 "auto_expand_replicas": "0-1",
 "provided_name": ".internal.alerts-default.alerts-default-000001",
 "creation_date": "1751520484817",
 "number_of_replicas": "1",

```

Do you have only 1 datanode because of which the replicas is by default set to 0?

You can check the settings of the index in your environment :

`GET /.internal.alerts-default.alerts-default-000001/_settings`

Are you observing any errors in the log?

Thanks!!