ECK 8.17.3 can't set replication factor on system indices

Elastic Stack Elasticsearch
1

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!

2

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.

"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!!