Change a cluster setting

Command

PUT /_cluster/settings
{
  "persistent": {
    "indices.recovery.max_bytes_per_sec": "100mb"
  }
}

What it does

Changes a persistent or transient cluster-wide setting.

When to use it

When tuning cluster behavior such as recovery speed.

Caution

persistent settings survive restarts; transient settings are lost and are deprecated since 7.16, so do not use them. To reset a setting to its default, set its value to null. A wrong value affects cluster stability.