Opster Team

July 2020, Version: 1.7-7.9

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Persistent in Elasticsearch

What it is:

In Elasticsearch, Persistent refers to cluster settings that persist across cluster restarts. This setting is used in Cluster Update API calls. Persistent settings can also be configured in elasticsearch.yml file.

Examples:

## enable shard routing
PUT /_cluster/settings
{
    "persistent" : {
        "cluster.routing.allocation.enable" : "all"
    }
}
## enable rebalancing of shards
PUT /_cluster/settings
{
    "persistent" : {
        "cluster.routing.rebalance.enable" : "all"
    }
}
## limit the heap size for fielddata
PUT /_cluster/settings
{
    "persistent" : {
                 “indices.breaker.fielddata.limit”: "30%"
    }
}